Mali President Ibrahim Boubacar Keita on Friday said his country "will do everything possible" in collaboration with France, Burkina Faso and Algeria to find circumstances that led to the crash of Air Algeria's flight AH- 5017 in northern Mali.

He made the pledge after visiting the crash site on Friday to "express the sympathy of the Malian people" to friendly countries whose citizens had perished in the tragedy.

"The least a president of a country can do is to visit the crash site. We have come to pay our last respect to the victims and express solidarity with the concerned countries," he added.

He promised that "everything will be done to ensure victims' bodies are repatriated to their countries in good conditions."

Malian authorities confirmed that investigations by air safety experts had been launched to find out the real cause of the accident, and that one of the black boxes had been retrieved.

The jet disappeared from the radar screen 50 minutes after it took off from Ouagadougou, capital of Burkina Faso, en route to Algiers on Thursday.

The plane crashed on Thursday morning in northern Mali, with more than 100 passengers on board.