At least one Briton was among the passengers on board a plane that crashed in Libya, killing at least 104 people, the Foreign Office confirms.
The Afriqiyah Airways flight from Johannesburg crashed at Tripoli International Airport.
Some passengers were due to connect with flights to Europe, including seven people booked onwards to Gatwick, South African air officials said.
Concerned relatives should call the helpline on +44 20 3355 2737.
The British Embassy in Libya said it had a consular team at the crash scene, but it had no information, as yet, of any other British passengers.
Officials were trying to get hold of a copy of the passenger list, a spokesman added.
At least 93 passengers were on board the Airbus 330. They are believed to be of various nationalities, including British, Dutch and South African.
'Urgently investigating'
The 11 crew were all thought to be Libyan nationals, an employee said.
The BBC's Rana Jawad in Tripoli says it was not clear whether the plane was on the runway when it crashed, but people at the airport told her they could not see the plane.
The Foreign Office said: "Afriqiyah Airways Flight 8U771 from Johannesburg had been due to land at 0610 local (0410 GMT). The plane crashed close to the airport".
A Foreign Office spokesman said: "Libyan officials have informed us that Afriqiyah Flight 8U771 from Johannesburg crashed at Tripoli International Airport this morning.
"Afriqiyah Airways have set up a helpline for those concerned about relatives".
BBC News
