Terminal 3 at Heathrow Airport has been evacuated following a fire alert.
The alarms went off at around 1pm and thousands of people were forced to leave the airport terminal.
Heathrow Airport says it is investigating the situation.
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It appears as though all is well now at Heathrow after a fire alarm caused the evacuation of Terminal 3 earlier today.
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Everything back to normal
It appears as though everything has gone back to normal at Heathrow’s Terminal 3 after an earlier evacuation.
Images on Twitter show the crowds gathering outside the airport
Evacuation could easily have led to 'chaos' says passenger
Ghian Tjandaputra also criticised the evacuation process.
“International terminal of one of the busiest airports yet hundreds had to exit through two narrow emergency doors.
“Credit to passengers calmly queuing.
“Alarming lack of info from staff, could easily lead to chaos if people were rushing in bottleneck.
“Once evacuated outside, bad could’ve turned worse in extreme heat or snow, especially for the elderly and children. Shelter needed.”
Airport travellers did not know where to go during alarm
Passenger's fear of what would have happened had there really been a fire
Faruk Miah’s flight was delayed during the disruption.
“I wasn’t happy with the evacuation procedure, especially as everyone seemed edgy after Grenfell.
“Our flight is being delayed to give enough time for people to check in.
“My worry is missing my connection in Dubai.
“Things have calmed now. No damage done, my flight is delayed but what was scary is, if it was a real fire, there would be serious casualties.”
Fire alert was a 'false alarm'
A Heathrow Airport spokesperson said:
“Terminal 3 was evacuated due to a fire alarm.
“This was a false alarm and we apologise for any inconvenience caused.
“Passengers will shortly be allowed back inside the terminal following this incident.”
Passenger describes 'complete confusion'
Dan, from Swindon, posted on social media:
“Heathrow Terminal 3 evacuated yet complete confusion.
“Some fire exits wont open.
“No help or communication from staff.”
Passengers waited while fire alarms sounded
Another passenger branded the airport staff handling as a 'shambles'
Video shows packed corridors of passengers
Passenger tweets that flight is 'suspended'
The Twitter user @weavbe wrote from the plane at 1.02pm:
“We were in the middle of boarding processed and they suspended all boarding.
“No info from the crew.”
Meanwhile, elsewhere in London a major train station has been evacuated
Passengers attempting to board flights describe 'chaos'
Heathrow Airport announced the evacuation at around 1pm
A statement said:
“T3 has been evacuated following a fire alarm.
“We are investigating this as a matter of urgency and will provide an update shortly.”