Heathrow and Gatwick LIVE: Flights grounded as air traffic control tech failure sparks chaos at airports

Heathrow airport has lost its position as Europe’s busiest airport to Istanbul, new figures show (Stefan Rousseau/PA)PA WireFights are reportedly grounded at London’s two busiest airports with passengers left stranded.A NATS spokesperson said in a statement on social media: “We are investigating a technical issue which is causing some disruption to flight departures.“Our engineers are on site and we will provide an update as soon as we can.“We apologise for the delay this will cause to journeys, passengers should check with their airline on the status of their flight.”Follow the latest updates below...Tube and Overground updateThere is now a good service on the vast majority of the Tube and Overground.There are only minor delays on both the Central and Circle lines due to train cancellations.Faulty train causes Metropolitan line delaysThe Metropolitan line is dealing with severe delays between Harrow-on-the-Hill and Aldgate, and minor delays between Harrow-on-the-Hill and Uxbridge, due to an earlier faulty train at Finchley Road. Tickets are being accepted on London Buses. There is a good service on the rest of the line. District line updateThere are currently severe delays on the District line between Earl's Court and Wimbledon, Richmond, and Ealing Broadway due to an earlier faulty train at Embankment. Tickets are being accepted on London Buses, Mildmay line, Elizabeth line and South Western Railway services. There is a good service on the rest of the line. DLR delaysThere are minor delays on the DLR due to an earlier signalling system failure. Hammersmith and City line delaysThe Hammersmith and City line is experiencing minor delays eastbound only due to train cancellations. There is a good service on the westbound line.Delays on London tramsThere are minor delays on the London Tramlink between East Croydon and Sundowns due to an earlier broken down road vehicle at Lebanon Road. There is a good service on other tram routes. Northern line updateThere are severe delays on the Northern Line between Camden Town and Edgware due to a fire alert at Hendon Central. There is a good service on the rest of the line. Windrush line delaysThere are severe delays on the Windrush line between Highbury & Islington and Dalston Junction due to a faulty train at Anerley. There are minor delays on the rest of the line. Metropolitan line updateThe Metropolitan Line is now suspended between Amersham and Chalfont & Latimer due to the signal failure at Chorleywood. There are also minor delays between Chesham and Rickmansworth, while there is a good service on the rest of the line. Tickets are being accepted on Chiltern Railways services.Central line updateThere are minor delays on the Central Line between White City and Ealing Broadway & West Ruislip and between Leytonstone and Epping& Hainault via Newbury Park due to train cancellations.There is a good service on the rest of the line.