Rescuers were on Tuesday set to resume the search for a plane carrying 43 people, including three Britons and an American, which crashed in the mountains of northern Afghanistan.
It was unclear whether there were any survivors from Monday's crash. The Pamir Airways plane had been en route from the northern province of Kunduz to Kabul when it came down over the treacherous Hindu Kush mountains, shrouded in heavy snow.
"I can confirm that a Pamir Airways plane has crashed over the Salang mountains with 38 passengers and five crew members on board," interior ministry spokesman Zemarai Bashary told AFP.
Dozens of Afghan police and local residents had started to climb the snow-capped mountains where the plane was believed to have crashed, Abdul Rehmand Sayeedkhaili, police chief of Parwan province, told AFP on Monday.
A highway task force, responsible for clearing snow from the Salang mountain pass -- the main road from Kabul to northern Afghanistan -- reported hearing a blast at around the time the plane went missing, Sayeedkhaili said.
Snow, cold weather and the harsh terrain made the search operation difficult, he said, with nightfall forcing a halt to their efforts.
NATO's International Security Assistance Force (ISAF), fighting against the Taliban, said it was assisting with the recovery operation.
"A manned ISAF fixed-wing aircraft has been dispatched to the last known position of the missing plane. However, the poor weather conditions in the area are hampering the aerial search," the military said.
"Two ISAF helicopters are en route to the area. Other ISAF helicopters are also on standby... to assist in any rescue effort," it said.
According to the passenger manifest of the plane seen by AFP, six were foreigners and the rest Afghans. A British embassy spokeswoman confirmed that three British citizens were on board while the US State Department said one American was on the plane.
A Turkish aid organisation, the IHH, said two of its employees -- both Turkish men -- were on board the ill-fated plane, but there was no immediate confirmation from the Turkish foreign ministry.
Acting transport minister Mohammadullah Batash said the aircraft lost radio contact 37 minutes after taking off on a return journey to the capital -- normally around an hour's flying.
"The plane left Kabul at 6:40 am (0210 GMT) and took off from Kunduz at 8:30 am back to Kabul, but lost radio contact at 9:07 am," Batash said.
The minister, who went to the suspected crash site in the Salang mountains to oversee the search for the wreckage and any survivors, said the cause of the crash was not clear. Poor weather could have been a contributing factor.
"We have to recover the black box to determine the cause," Batash said.
"We cannot rule out any of the usual causes behind crashes -- which could be bad weather, technical error, thunder and lightning or even terrorist attacks," he said.
Yalda Natiq, director of communications at the transport ministry, said the Antonov 24, which is a Soviet-made turboprop plane, crashed due to bad weather.
According to its website, Pamir Airways was founded in May 1995 and is the oldest private airline in Afghanistan.
Commercial aviation incidents are rare in Afghanistan, where travel by road can be hazardous due to the nearly nine-year Taliban insurgency.
In February 2005, a Boeing 737 operated by private company Kam Air crashed in the mountains on the outskirts of Kabul during heavy snow. There were 104 people on board, including two dozen foreigners. There were no survivors.