A plane heading for the Everest region has crashed in the Nepalese capital, killing all 19 people on board. The plane, operated by Sita Air, came down minutes after take-off from Kathmandu. Officials said it crashed into a river bank and caught fire. Sixteen passengers - at least 12 of whom were said to be foreign nationals - and three crew were on board the twin-engine prop plane. It was on its way to Lukla, the hub for trekking in the Everest region. A spokeswoman for the UK Foreign and Commonwealth Office said: "We understand that British nationals may be involved, and we are urgently seeking to confirm what has happened. "Our embassy in Kathmandu is talking to the airline and local authorities to find out whether Britons were involved." Police spokesman Binod Singh told the AFP news agency that "the pilots seem to have tried to land it safely on the banks of the river but unfortunately the plane caught fire". The cause of the crash is not yet known but conditions were said to be clear at the time. Aviation accidents involving small aircraft are not uncommon in mountainous Nepal. In May, 15 people were killed when a plane crashed trying to land at an airport in the north of the country.