Rochester, MN (KROC AM News) -The Rochester Fire Dept. is investigating what appears to be a suspicious incident.

Crews were sent to the Olympik Apartments complex at 402 31st Street NE around 3:30 AM Thursday after fire alarms were activated.

According to the department, “3 small rugs had been started on fire, one on each floor in the hallways” of one of the buildings.

The department says tenants had used extinguishers and water to douse the fires before RFD crews arrived.

RFD had all occupants evacuate or remain in their apartments until the hallways were ventilated.

Rochester police investigators are working with RFD on what has become an arson investigation. Lt. Mike Sadauskis says there were indicators that an accelerant was used to start the rugs on fire.

News Update: Rochester man is sentenced for sexually abusing young girl at Rochester Y.