A mass shooting on Thursday at Western Psychiatric Institute and Clinic in Pittsburgh, U.S. state of Pennsylvania, has killed two people and wounded seven others, according to a report by local TV station WPXI-TV.

The shooting happened in the afternoon in the hospital lobby. Investigators said two people, including the gunman were killed. The shooter was found dead in a hospital hallway after being wounded by the police.

Seven other people were injured, including a University of Pittsburgh officer, who was grazed in the leg. There is no word about their conditions.

A SWAT team was sent to sweep the building to make sure the situation is completely clear. Authorities conducted a room-by- room search of the complexes as a precaution. At least 200 police officers were sent to or around the scene.

Officials said after searching the building, there was no indication that another gunman was in the building.

Police said initial reports indicated that gunmen may have been holding people hostage inside of the hospital, but later found out those reports were unfounded.

The entire University of Pittsburgh and Pittsburgh Public School's Science and Technology Academy were placed on lockdown.

VietNamNet/Xinhuanet