These vehicles are part of the Butler Bureau of Fire fleet. Butler Eagle file photo

No one was home when the Butler Bureau of Fire responded to a call for a fire at 331 East Brady St. at around 8:30 a.m. Monday.

A captain with the bureau said the crew found a fire on the right side of the basement of the duplex after entering the secured building following a call from a passerby. The basement sustained minor-to-moderate damage, according to the captain.

Firefighters said the tenants of the duplex were in the process of moving out of the building when the incident was reported, and investigators are still trying to determine the cause of the fire. Firefighters cleared the scene by around 10 a.m.