Fresno firefighters responded early Tuesday to a fire at Valley Fitness on the 3000 block of North Maroa Avenue, officials said.
Crews arrived just after 4:30 a.m. to flames visible on the gym’s roof, the Fresno Fire Department said in a statement.
Firefighters quickly determined the fire had started inside the building and burned through to the roof.
Due to the size of the structure and the intensity of the blaze, a second alarm was called, bringing roughly 50 firefighters to the scene, the department said.
The gym was closed at the time of the fire. The department said one firefighter was hurt while fighting the blaze and was taken to a hospital.
Officials said the building suffered significant damage and will remain closed indefinitely. Fire crews continued to work at the site throughout the day.
The cause of the fire is under investigation.
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