Montgomery Fire/Rescue spent part of the afternoon battling a structure fire on Highland Avenue. Firefighters responded to the 1500 block just before 3:30PM on a three-alarm fire. District Chief Quentin Burke tells Alabama News Network that it appears to be a vacant warehouse. Chief Burke says more than 50 firefighters were on hand to help extinguish the flames. Three firefighters were transported to a local hospital due to heat-related injuries. The cause of the fire is under investigation.