Hillsborough County firefighters battled an apartment complex blaze on Saturday where several units caught fire.Hillsborough County Fire Rescue responded to the apartment complex at about 10:47 p.m. at 209 Monastery Court, Valrico, after receiving multiple 911 calls reporting heavy smoke and visible flames.The first crew arrived at the scene in under four minutes where several of the units had caught fire, some already engulfed in flames, according to a Fire Rescue press release.Firefighters brought the fire under control in under an hour, preventing further damage to the surrounding units, fire officials said.No injuries to residents or firefighters were reported.The cause of the fire is currently under investigation.