CINCINNATI (CBS) — Three people were killed in a shooting at the Fifth Third Bank building in downtown Cincinnati, the police said. The gunman was also dead, but it’s unknown if he was shot by police or he shot himself, police said at a press conference.

Police Chief Eliot Isaac said the shooter opened fire early Thursday morning at the building’s loading dock. Isaac said the gunman then entered the bank’s lobby, where he exchanged gunfire with the police.

The situation appeared to be under control shortly before 10 a.m. ET but police said they are still investigating. A spokeswoman for University of Cincinnati Medical Center told CBS affiliate WKRC-TV that four victims had been transported to the hospital.

The hospital later said on Twitter that two of the four victims had died, another was in critical condition and the fourth was in serious condition. All four had suffered gunshot wounds.

A WKRC-TV reporter posted pictures to Twitter showing police responding to the scene of the shooting. Streets and sidewalks around the building at the city’s Fountain Square were closed.

People in and around the building reported hearing a series of gunshots. Federal agents were on the scene.

This is a developing story and will be updated.