Armed police carried out searches on flights departing Heathrow Airport after planes were temporarily grounded following a security alert at Terminal 3 this morning.
Hundreds of passengers' travel plans were affected after a "suspicious item" was detected by an X-ray scan of baggage at the hub airport on Friday (May 5), the Metropolitan Police said.
It is believed flights were suspended for at least two hours while the incident was dealt with.
One passenger affected by the delays was on a British Airways flight to Bilboa, Spain.
He told the Press Association his plane was held on the tarmac for two hours due to a suspected "security lapse", with each departing aircraft being searched by armed police.
Mr Chambers said the captain on his flight told passengers the delays were due to an incident involving a man who grabbed his bag and ran through security after it had been pulled aside to be checked.
Citing the captain, Mr Chambers said as a result, all flights from Terminal 3 were grounded.
While it was initially feared the passenger had run back on to the airside area of security from arrivals, it was later confirmed this was not the case.
Passengers said they were faced with long queues at the airport and lack of information.
A Heathrow Airport spokeswoman said: "Departures were suspended from Terminal 3 earlier this morning due to a security issue.
"We are very sorry to any passengers whose journeys are affected.
"The safety and security of our passengers and colleagues is paramount."
A Metropolitan Police spokesman added: "Police were called at approximately 8am to Heathrow Terminal 3 following a report of a suspicious item detected by an X-ray of luggage.
"Officers are working with the airport authorities and inquiries are continuing.
No arrests have been made.
Terminal 3 has since re-opened.
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