At least six people have injured in a shooting at a Greyhound bus station in Virginia.
Earlier reports said one state trooper was killed but he has been transferred to hospital in a critical condition.
A witness described hearing a series of loud bangs and flashes of light. He said people then started to run from the building.
The injured, including the state trooper and a female civilian, and have been transported to a local hospital for treatment, according to ABC 8.
Virginia State Police have said the attacker was shot dead.
State police were conducting a training exercise at the bus station the time of the incident.
A local councilwoman, Reva Trammell, has said it is "the saddest day in Richmond".
Police were called to the scene at around 2:45pm (7:45pm UK time) in the city of Richmond.
Brendan Hamilton told The Richmond Times-Dispatch newspaper that he was about to walk into the station when he heard two loud bangs, then saw flashes of light.
He said he then heard at least five more bangs and people then started to run out of the building.
Michael Bickett, who works nearby said in a direct Twitter message: "A co-worker was eating lunch in his car when he saw Greyhound Workers and customers rushing out the side door.
"He figured that was a good time to get back inside."
A spokeswoman for Greyhound told CNN the station was now closed until further notice.
Greyhound buses have been arriving at the depot but have been unable to get inside and a large of number of police are visible at the scene.
Additional reporting by agencies
