Two firefighters were injured while fighting a fire at a Tampa nightclub.

The fire broke out Wednesday night at Amphitheater Club in Ybor City. Before the night was over, nearly 20 units and 50 firefighters responded to the fire.

Tampa Fire Rescue spokesman Jason Penny says three workers inside the building got out safely and neighboring buildings were evacuated. Officials believe a welder was doing work on the two-story building when an arc ignited material covering the ceiling. The fire quickly spread.

Penny says an automatic sprinkler system was triggered but it wasn't enough to douse the flames. The fire raged for almost six hours.

The firefighters were taken to a hospital for observation.

The fire marshal's office is investigating.

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