A passenger bus has collided with a fuel tanker in Afghanistan, killing 50 people and injuring several others, with women and children among the victims, officials said.

The incident happened on Friday  in the Spin Band area of Ab Band district of Ghazni province, which straddles the main highway from Kabul to Kandahar, the capital of the south.

It was not immediately clear to whom the fuel tanker belonged.

Ghazni is part of the main supply route for NATO goods coming into Afghanistan from the north and heading south.

"At around 6:30 am [0200 GMT] a passenger bus collided with a fuel tanker in the Spin Band area of Ab Band," Mohammad Ali Ahmadi, the deputy governor of the province, told the AFP news agency.

"As a result, the fuel tanker and the passenger bus caught fire and 50 people were killed and six others were wounded in the collision. There are women and children among the victims," he said.

The interior ministry also said that 50 people had died in the incident.