Algeria’s defence ministry has blamed “very bad weather conditions, involving a storm and heavy snowfall” for the crash, yesterday, of a military passenger plane, killing all but one of the 78 people on board.

The flight’s departure point was the Sahara Desert garrison city of Tamanrasset, 1,500km (950 miles) south of Constantine. It made a stop in Ouargla.

A source told radio station Ennahar – which has close links to the government and army – that contact was lost with the military plane between Oum al-Bouaghi and Constantine as it was descending to land.

It crashed into Djebel Fertas mountain, some 380km (240 miles) east of the capital Algiers.

“The plane crashed into a mountain and exploded,” an official told Reuters.

It is the worst plane crash in Algeria for more than 10 years and the third involving an Algerian military Hercules Boeing 737 which crashed on take-off from Tamanrasset in 2003, killing all but one of the 103 people on board.

A BBC report quotes the Algerian defence ministry as saying in a statement that it has set up a commission to investigate yesterday’s crash and that Ahmed Gaid Salah, who is both army chief of staff and deputy defence minister, would go to the crash site.

Security sources and state media originally reported 103 people on board the flight, but the number was later revised down by the military to 78. Most of the 78 passengers were military personnel and their family members. Women and children were among the bodies recovered from the crash site. The lone survivor, a soldier, is reportedly being treated for head injuries at a military hospital in Constantine.

President Abdelaziz Bouteflika has praised the soldiers who died in the crash as “martyrs” even as the country begins three days of national mourning for the victims.

•Photo shows wreckage of the plane.