Kabul, Afghanistan (CNN) -- An airplane with 44 people on board has crashed in the mountains of Afghanistan, an Afghan government spokesman said Monday.
The plane was carrying 38 passengers and six crew members when it crashed en route from Kunduz to Kabul, said Raz Mohammad Alami of the Ministry of Transport and Civil Aviation.
Several non-Afghans were on the plane, which has not yet been found, said Zemarai Basharay, a spokesman for the Interior Ministry.
At least three of them were British nationals, according to a Foreign Office spokeswoman who declined to give her name in keeping with the office's typical practice.
The plane crashed near the Salang Pass, north of Kabul, he said. A meteorological agency reported hearing a huge sound there, and the government's minister of transport and aviation and his deputy went there to investigate.
The NATO-led International Security Assistance Force has sent a plane to the region, said spokesman Col. Wayne Shanks, but the search has been hampered by rain and adverse weather conditions.
In addition, the force sent two helicopters to the area, and others were on standby at Bagram Airfield and Kabul International Airport, the NATO-led force said.
While several plane crashes have occurred in Afghanistan in the past few years -- most of them military aircraft -- the last crash with fatalities occurred in September 2006, when a British Royal Air Force plane crashed about 12.5 miles (20 km) west of Kandahar, according to the website of the Aviation Safety Network, which maintains a database of crashes. Fourteen people were killed in that crash.
In 2005, 104 people were killed when Kam Air flight 904 struck a mountain while approaching Kabul in poor visibility, according to the network.
CNN's Atia Abawi and Journalist Matiullah Mati contributed to this report.