A Lufthansa jet was forced to abort a take-off from New York's JFK airport after an Egyptian plane on the ground strayed too close to the runway.
"Cancel take-off plans," the American air traffic control official shouted over the radio.
A US air traffic official said an EgyptAir jet was told to remain 250ft (76m) from the runway the Lufthansa plane was using, but moved too close.
The Lufthansa jet braked quickly after being ordered to stop by air traffic.
Radio chatter indicates the pilot slammed on the plane's brakes after being ordered to come to a stop.
US aviation authorities are now investigating how the near-miss came about.
The Munich-bound Lufthansa plane, an Airbus A340, was carrying 286 passengers, while the Egypt air jet was a Boeing 777, the New York Post reported.
Kathleen Bergen, a spokeswoman for the Federal Aviation Administration, told the Associated Press the Lufthansa plane stopped "a considerable distance" from EgyptAir flight 986.
After the Lufthansa plane halted, the pilot said he had "hot brakes" and needed to take a minute. The tower controller then said a maintenance crew would inspect them.
Then, a man identified as a pilot for a Virgin America plane said on the radio: "That was quite a show. We thought it was going be a short career."
A US passenger jet bound for Moscow has returned safely to a New York airport after reports its wing had caught fire.Emergency crews were sent to New York's JFK airport to wait for the plane
by Suzanne Gould and Biodun Iginla, BBC News
The Delta Airlines Boeing 767 dumped fuel and turned back to John F Kennedy Airport after reports of engine trouble soon after take-off.
Emergency crews were sent to the airport to wait for the plane - which had 200 passengers on board - to land.
A fire official said there were no signs of fire once the plane landed, and no injuries were reported.
The jet landed at JFK airport at 1750 (2250 GMT).
A Federal Aviation Administration spokeswoman said the incident was being investigated.
One of the two parcel bombs intercepted last week after being sent from Yemen was defused 17 minutes before it was due to go off, France's Interior Minister Brice Hortefeux has said.
Mr Hortefeux was speaking to France-2 television but did not reveal his source for the information.
The two bombs were sent via air freight to the US but intercepted in Dubai and the UK and defused.
Investigators have focused on a Yemen-based al-Qaeda offshoot.
The group, Al-Qaeda in the Arabian Peninsula (AQAP) has said it was behind the parcel bomb plot.
Security forces in Yemen are hunting for suspected bombmaker Ibrahim al-Asiri, who is suspected of being behind last year's failed 25 December attempt to bomb a US airliner and other attacks.
The bombs were found after a tip-off from Saudi authorities and were pulled off US-bound cargo planes in England and Dubai.
The bombs were made of a difficult-to-detect explosive called PETN, and concealed within printer cartridges inside larger packages.
Police and investigators look at what remains of the flight deck of Pan Am 103 on a field in Lockerbie, ScotlandPhoto: AP
Both bombs found last week had been transported in the hold of passenger flights, suggesting that the terrorists were targeting tourists and other travellers, rather than simply trying to bring down cargo planes, as had previously been thought.
A device found at East Midlands airport on Friday had left Yemen on a passenger aircraft, The Daily Telegraph has learnt, before it was switched to a UPS cargo plane. The second device, found in Dubai, was carried on two Qatar Airways passenger flights before it was intercepted.
Sources close to the investigation in Yemen said because there were no scheduled cargo flights out of the country it was likely the terrorists knew the bombs would be loaded on to passenger planes for at least part of their journey.
Theresa May, the Home Secretary, also admitted yesterday it was possible that the US-bound bomb found at East Midlands could have detonated over Britain if it had not been found, because of the unpredictability of freight routes.
In further developments:
* A woman was being hunted in Yemen after posting the bombs, using an identity stolen from a student.
* Investigators in Yemen said they were examining 26 other suspect packages.
* British police faced criticism from the US over their failure to find the East Midlands device during their initial search.
* Downing Street was forced to defend David Cameron’s decision to say nothing about the bomb plot for more than 24 hours.
* The airline pilots’ union said it had been warning for years of cargo being a weak link in air travel that could be exploited by terrorists.
The two bombs, concealed inside computer printers, were virtually impossible to detect by X-ray screening because they contained an odourless explosive and used timers that would have looked like part of the printers’ electronics.
They were designed to explode in mid-air and would have been as capable of bringing down an aircraft as the device that blew up PanAm Flight 103 over Lockerbie in 1988, killing 270 people.
More than half of all freight to the US is carried on passenger flights and Lord Carlisle of Berriew, the former government adviser on terrorism, said there was every chance a parcel bomb could end up on a passenger plane.
“If you put a parcel into UPS, you have no way of knowing what flight it is going to go on,” he said. “It could end up on a passenger flight.”
One of the bombs went to Dubai via Doha in Qatar on a passenger aircraft. The device that was found at East Midlands airport left the Yemeni capital of Sana’a on a passenger aircraft, which is also thought to have stopped at Doha, before it travelled to Cologne in Germany and Britain in cargo planes. Mrs May said: “What became clear overnight on Friday and into Saturday was that it was indeed a viable device and could have exploded.
“It could have exploded on the aircraft, and it could have exploded when the aircraft was in mid air. Had that happened it could have brought the aircraft down.”
Mrs May said it was “difficult” to say whether the explosion would have happened over Britain or America. “With these freight flights sometimes the routing can change at the last moment so it is difficult for those who are planning the detonation to know exactly where — if it is detonated to a time, for example — the aircraft will be,” she added
After investigators in Yemen confirmed that they were examining 26 other packages, John Brennan, President Barack Obama’s counter- terrorism adviser, said “it would be very imprudent … to presume that there are no other” [bombs].
Mr Brennan described the bombs as “sophisticated”, adding: “They were self-contained. They were able to be detonated at a time of the terrorists’ choosing.”
He said the plot “bears the hallmark” of al-Qaeda in the Arabian Peninsula (AQAP), the terrorist organisation’s Yemeni-based operation, whose leaders include Anwar al-Awlaki, an American-born preacher.
The most likely bomb maker is said to be Ibrahim Hassan al-Asiri, who made the device used in the foiled Christmas airline attack over Detroit.
The bombs, which were addressed to two synagogues in Chicago, contained the contact details of a 22-year-old computing student, Hannan al-Samawi, who was arrested on Saturday night.
However, investigators released her yesterday and said they were now seeking another woman who it was thought had posted the devices using Miss al-Samawi’s personal details.
Intelligence that foiled the plot may have come from Jabir Jubran al-Fayfi, a former leading member of AQAP, who surrendered to the Saudi authorities last month.
In light of the plot, the US National Transportation Safety Board is re-examining the wreckage of a UPS cargo jet that crashed in Dubai in September, although sources in Dubai said there was no evidence of an explosion.
American officials expressed concern at the fact that the bomb at East Midlands was discovered only during a second police search.
David Cameron said the Government would “take whatever steps are necessary” to keep British people safe, but Downing Street was forced on to the defensive after the Prime Minister took until 6pm on Saturday – 26 hours after he was first briefed on the incident – to make a public statement.
It was left to Mr Obama, and later Mrs May, to break the news that viable devices had been found. Sources said Mr Cameron “wanted ministers to take the lead”.
Balpa, the pilots’ union, said it had warned for years of the threat from cargo, suggesting that the focus on checking passengers and their luggage “left the door open” for attacks by other means.
In Yemen, police have arrested a woman suspected of posting the packages.
She was detained in the capital, Sanaa, after being traced through a telephone number she had left with a cargo company, officials said.
The unnamed young woman, described as a medical student and the daughter of a petroleum engineer, was arrested along with her mother on the outskirts of the city, a security official told AFP news agency.
President Ali Abdullah Saleh said the US and the United Arab Emirates had provided Yemen with information that helped identify the woman and pledged that his country would continue fighting al-Qaeda "in co-operation with its partners".
"But we do not want anyone to interfere in Yemeni affairs by hunting down al-Qaeda," he added, as heavily armed troops patrolled Sanaa.
The Yemeni authorities also closed down the local offices of the US cargo firms UPS and FedEx, who had already suspended all shipments out of the country and pledged full co-operation with investigators.
US President Barack Obama's national security adviser, John Brennan, has phoned Mr Saleh to offer US help in fighting al-Qaeda, the White House said.
The US authorities have been impressed by the speed and determination the Yemeni authorities have shown in their response, the BBC's Jon Leyne reports from Cairo.
The explosive devices, which triggered security alerts in the US, UK and Middle East, were apparently both inserted in printer cartridges and placed in packages addressed to synagogues in the Chicago area.
Pentaerythritol tetranitrate (PETN) - an explosive favoured by the Yemeni-based militant group, al-Qaeda in the Arabian Peninsula (AQAP) - was discovered in the device intercepted in Dubai.
Mr Obama discussed the apparent terrorist plot with Mr Cameron by phone on Saturday, expressing his "appreciation for the professionalism of American and British services involved" in disrupting it, the White House said.
'Professional manner'
Later, Mr Cameron told reporters at his country residence, Chequers, that it was believed the explosive device intercepted at East Midlands Airport was "designed to go off on the aeroplane".
David Cameron: "We believe the device was designed to go off on the aeroplane"
"We cannot be sure about when that was supposed to take place," he added.
"There is no early evidence that it was meant to take place over British soil, but of course we cannot rule it out."
The prime minister said the authorities had immediately banned packages coming to or through the UK from Yemen, and would be "looking extremely carefully at any further steps we have to take".
UK Home Secretary Theresa May said the government did not believe the plotters would have known the location of the device when it was planned to explode.
While details of the device found in Britain were not released, photographs emerged on the US media of an ink toner cartridge covered in white powder and connected to a circuit board.
The British government's remarks suggest the authorities in both the UK and the US remain uncertain about the precise targets and, indeed, aim of this latest apparent plot, BBC defence and security correspondent Nick Childs reports.
Parcels could be seen stacked outside Sanaa airport on Saturday
According to Dubai police, the explosives they found were also inside the toner cartridge of a printer, placed in a cardboard box containing English-language books and souvenirs.
The cartridge contained PETN and plastic explosives mixed with lead azide, they said. Lead azide is an explosive commonly used in detonators.
"The device was prepared in a professional manner and equipped with an electrical circuit linked to a mobile telephone [Sim] card concealed in the printer," the police said.
For US Homeland Security Secretary Janet Napolitano, the plot bore "all the hallmarks of al-Qaeda and in particular [AQAP]".
Unnamed US officials quoted by the Associated Press said al-Qaeda's explosives expert in Yemen, Ibrahim Hassan al-Asiri, was the likely suspect behind the bomb-making.
They said Mr Asiri had helped make the bomb used in the failed Detroit Christmas bomb attack and another PETN device used in a failed suicide attack against a top Saudi counter-terrorism official last year.
The White House has said Saudi Arabia provided information that helped identify the threat, while the UK's Daily Telegraph reported that an MI6 officer responsible for Yemen had received a tip-off.
How the alerts were raised (all times GMT):
• Early hours of Friday morning: alert raised at East Midlands airport after suspect package found on UPS plane. Security cordon put in place, then lifted.
• 0900: suspect package found on FedEx plane in Dubai.
• 1300: security cordon reinstated at East Midlands airport, apparently after a second suspect device is found.
• 1700: FBI says two suspect packages were addressed to religious buildings in Chicago.
• 1835: Emirates Flight 201 from Yemen via Dubai lands at JFK airport, New York, escorted by US fighter jets. The plane is carrying a package from Yemen.
• 1845: FedEx in Dubai confirms it has confiscated a suspect package sent from Yemen and is suspending all shipments from Dubai.
• 1900: two other FedEx flights investigated after landing at Newark, New Jersey, and Philadelphia. Both receive the all-clear.
• 2330: BA flight from London to New York (JFK) met by US officials as a "precautionary measure".
LONDON – The chairman of British Airways has criticized airport checks as "completely redundant" and said Britain should stop "kowtowing" to U.S. demands for increased security, the Financial Times reported on Wednesday.
The newspaper quoted Martin Broughton as saying at the annual conference of the UK Airport Operators Association in London on Tuesday that no one wanted weak security.
Broughton said, however, the practice of forcing people to take off their shoes and have their laptops checked separately in security linesshould be ditched.
"We all know there's quite a number of elements in the security program which are completely redundant," he said.
Broughton said there was no need to "kowtow to the Americans every time they wanted something done" to beef up security on U.S.-bound flights, especially when this involved checks the United States did not impose on its own domestic routes.
"America does not do internally a lot of the things they demand that we do. We shouldn't stand for that," he said.
"We should say, "We'll only do things which we consider to be essential and that you Americans also consider essential'."
The Financial Times said Broughton's comments reflected broader industry and passenger frustration over the steady accumulation of rules on everything from onboard liquids to hand baggage that had been adopted since the Sept 11, 2001 attacks.
No comment on Broughton's remarks was immediately available from British government or airport officials.
US & Canada 
New York's JFK airport is one of the busiest international airports in the US 
