Chinese media report that at least four people were killed Monday when an explosion ripped through a restaurant in the northwestern Chinese city of Xi'an.

The official Xinhua news agency said the blast occurred early Monday at a fast food restaurant on the first floor of Jiatian International Mansion, a commercial building in the city known for the Qin Dynasty terra cotta warriors.

Xinhua said at least 25 people were injured in the explosion, most of them passers-by.

The explosion damaged many cars and broke windows as far as three kilometers away.