The death toll from an oil tanker fire in Afghanistan's high-altitude Salang Pass tunnel has risen to 31, an official said on Monday, with dozens more suffering burn injuries.

The incident occurred late Saturday in Parwan province, north of Kabul, leaving travelers on both sides of the mountain pass stranded.

At least 31 people were killed, and 37 were injured in the incident, Sharafat Zaman Amar, spokesperson for the public health ministry, told AFP on Monday.

The toll was expected to rise further, he added.

The tanker overturned and caught fire in the tunnel, setting many other vehicles ablaze, officials said earlier.