Spanish police say four people are missing and four others have been injured in an explosion at a fireworks factory in northeastern Spain.

A police spokeswoman said the blast occurred around 2 p.m. (1200 GMT) Monday at the Pirotecnia Zaragozana factory in the small town of Pinseque.

The officer said police were searching the blast area for the four missing while the four injured had been taken to a hospital in the nearby regional capital of Zaragoza. The officer spoke on condition of anonymity in keeping with police regulations.