The military in Mali says more than 20 soldiers have been killed by suspected jihadists in the northern region of Gao.
People in the area said militants drove around their villages in cars and on motorbikes before attacking the army base at dawn on Monday.
They said the insurgents destroyed the camp near the town of Bamba and stole weapons.
An army official said jihadists had also been killed but it was impossible to tell how many as they had taken their dead and wounded with them when they left the area.
Jihadist attacks are intensifying across the Sahel.