(CBS) — A state trooper was killed in an exchange of gunfire at a Greyhound bus station in Richmond, Va., on Thursday.

CBS affiliate WTVR in Richmond reports that the gunman also died.

Virginia State Police spokeswoman Corinne N. Geller said four people, including the suspect, were shot.

The shooting happened around 2:45 p.m., Eastern time. Sources told WTVR state police were conducting a training exercise in the area at the time of the shooting.

Geller said the trooper was talking to the suspect when he pulled out a gun and shot the trooper, WTVR reported. Two civilians were also wounded.

Geller said two nearby troopers returned fire.

The Greyhound Bus Station is located west of the city’s downtown area, across from Richmond’s minor league baseball stadium and within a former industrial area.

It is located on a main thoroughfare connecting a residential district to the stadium and nearby restaurants.