After battling flames overnight, Hillsborough County crews remain at the scene of a massive scrapyard fire Friday morning. Just after 9:30 a.m. Thursday, crews arrived to heavy flames at Liberty Recycle, located at 5207 St. Paul Street in Tampa. As of 9:30 a.m. Friday, six Hillsborough County Fire Rescue units remain on scene to extinguish lingering hot spots. "The fire was brought under control at 12:15 a.m. after crews worked through the night to contain the flames fully," the agency wrote in an update. Smoke could be seen for miles on Thursday as crews used heavy machinery to move piles of debris and aerial units to dump water on the fire from above. "We saw a lot of dark smoke that could be indicative of tires or synthetics, and so that's the nature of the beast with these types of fire. We just don't really know what's in these stacks of rubble," HCFR Public Safety Information Chief Rob Herrin said. Two firefighters were transported to the hospital for injuries. Both are said to be stable. ​Officials have not released information on what may have caused the fire.