About 30 people have been displaced after an apartment fire in Rohnert Park. The fire broke out Saturday afternoon at an apartment complex in the 900 block of Kirsten Court. The fire had fully engulfed one unit on the second floor and was rapidly spreading to neighboring apartments. The apartment building’s lack of firewalls in the attic, due to its age, contributed to the rapid spread of the fire. Firefighters aggressively attacked the blaze, successfully bringing it under control in about an hour. The fire is believed to have originated in the living area of one apartment, though the exact cause remains under investigation. The building has been declared uninhabitable and about 30 people have been displaced. One firefighter was transported to the hospital for a medical evaluation. The fire is estimated to have caused about $2 million in damage.