Passengers arriving at Heathrow were affected by the problem which caused long queues to go through UK immigration, with reports of waits of up to two hours.
There are 25 e-gates in operation at Heathrow’s Terminal 5, which can process a passenger every 45 seconds when working.
The Home Office, which manages the e-gates, said the problem was caused by a “technical issue” affecting the barriers at several ports.
“We are working to resolve the issue as soon as possible and apologise to all passengers for the inconvenience caused,” said a Home Office spokesperson.
