At least 19 people were killed and 32 injured when a fuel tanker exploded in a tunnel north of the Afghan capital Kabul, AP reported, citing local authorities. 

The Salang Tunnel, about 80 miles north of Kabul, was originally built in the 1960s to aid Soviet forces. It is a key link between the north and south of the country.

Parwan provincial spokesman Syed Himatullah Shamim said at least 19 people, including women and children, were killed in Saturday night's tunnel explosion. He said survivors remain under the rubble and that the death toll could rise.

It is not yet clear what caused the incident, which occurred at about 8:30 p.m. local time. 

According to local official Dr. Abdullah Afgan, the Parwan Health Department received 14 dead and 24 wounded. He said five women and two children were among the dead, and the rest were men who were badly burned and could not be identified.

Molvi Public Works Ministry spokesman Hamidullah Misbah said earlier Sunday that the fire had been extinguished and that teams were still working to clear the tunnel.