JINAN - An oil tank exploded and caught fire in East China's Shandong province on Friday, local authorities said.

The blast happened around 9 am in a tank storage area in an industrial zone in Gaoliu township in the city of Qingzhou, a municipal firefighter said.

The number of casualties, if any, is not yet known.

Subsequent explosions are possible, as more tanks containing crude oil are located nearby, the firefighter said.

More than 10 fire trucks have been sent to the scene to put out the fire.

The cause of the blast is under investigation.