A mattress fire rekindled inside a Depew duplex this morning, resulting in an estimated $90,000 damage, according to village police.

The fire was reported at about 7:20 a.m. at 93 Patsy Lane. Emergency responders found one side of the structure engulfed, with flames coming from a second-story window.

Residents from both units were evacuated without injuries, police said.

Police investigators determined the fire started in an upper front bedroom, where a mattress caught fire as a resident was smoking in bed. The resident poured water on the mattress and then stood it in an upper hallway, believing the fire was out, police said.

After the resident left for work, other family members who were home smelled smoke. Someone went upstairs to investigate, and found the mattress had rekindled and the hallway was engulfed in flames.

Firefighters from Depew, Hyview and Bowsmanville quickly brought the fire under control, but the upper floor sustained major water damage, according to police.

Arson investigators from the Depew and Cheektowaga police departments believe the cause was accidental, pending the results of lab tests.