ROHNERT PARK (BCN) - Fire investigators suspect illegal fireworks sparked an apartment complex fire in Rohnert Park on Monday that left more than 30 displaced.

The blaze was reported at 4:37 p.m. at the Glen Manor Apartments at 6930 Commerce Blvd.

Emergency crews arrived to find smoke and flames coming through the roof, which later collapsed, fire officials said.

Fire officials said witnesses saw "loud, explosive, aerial fireworks, with bright flashes."

The apartment complex has a wood frame construction with wood siding, and wood shake roofing. It consists of multiple structures that contain a total of 12 units.

Some of the occupants had self-evacuated before fire crews responded and firefighters evacuated the remaining residents.

A firefighter was treated for heat exhaustion and released and no residents were injured in the blaze, fire officials said.

The fire was contained within two hours and all of the residents were displaced.

The American Red Cross and management for the apartment complex assisted the residents in finding temporary housing, fire officials said.

Investigators recovered evidence of illegal fireworks nearby the structure and are asking anyone with information to call the Rohnert Park Department of Public Safety at (707) 584-2630.

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