Initial investigations into a fire that killed nine people in east China's Zhejiang Province indicated arson was to blame, police said Tuesday.

Police said they had found evidence of arson, but did not elaborate.

The fire broke out at about 8:15 p.m. Monday in an 8-story residential building in the downtown area of Quzhou, 230 km southeast of the capital city of Hangzhou.

Eight men and one woman were killed at the scene and two were injured, police said.

The injured are receiving medical treatment in two hospitals and both are in stable condition.

The fire broke out in a ground-floor apartment. Witnesses heard a loud bang and thought a gas cylinder may have exploded.

The apartment was rented out to a local resident surnamed Zhang.

It is not clear if Zhang was among the dead.

Police are further investigating the cause of the accident.