Warwick police are investigating after a RIPTA bus slammed into a building in their community on Monday night.

According to a press release from Warwick Chief of Police Col. Stephen McCartney, the incident occurred shortly after 7 p.m. The bus is said to have collided with a pole before striking the building at 1207 Post Road, which houses a paintball shop and the Driver’s Seat automotive store.

Police said several witnesses were interviewed, and neither alcohol nor speed appeared to be a factor. Richard Avedisian, 51, of North Kingstown, a longtime employee of the agency, was operating the bus. He is not related to Warwick Mayor Scott Avedisian, the chair of RIPTA’s board.

It is believed the driver may have suffered a medical incident that played a role in the crash. He remained hospitalized in critical condition on Tuesday.

Three other people were aboard at the bus at the time of the incident, police said. Two were transported to Rhode Island Hospital, with one treated and released and the other also still hospitalized in critical condition on Tuesday. The third had left the scene prior to the arrival of emergency personnel, but has since been identified and interviewed by police.

Warwick building officials declared the building uninhabitable, and the investigation remained ongoing Tuesday. Warwick police asked anyone with information or who witnessed the incident to contact the lead investigator, Officer Robert Hart, at 401-468-4345.