HARTFORD, Conn. (WTNH) — The Hartford Fire Department is investigating a second alarm fire after a garage at Central Auto on Maxim Road went up in flames early Tuesday morning.

Now there are environmental concerns too.

At around 5:30 a.m., fire crews responded to Central Auto and Transport, at 195 Maxim Road, for a large fire.

The Hartford Fire Chief says crews are now monitoring the fire and letting it burn due to the amount of oil contributing to the fire.

The Fire Chief says there are two 50 gallon oil tanks and dozens of new tires in the burning building.

“There was a driver of one of the vehicles. Somehow he was moving out one of his trucks and it was on fire and then fuel oil was making a trial. He was able to get out,” said Rodney Barco, Asst. Chief Hartford Fire. “I’m not sure what started the fire, but we have the Fire Marshal on scene.”

“I heard an explosion. I didn’t think anything. I thought thundering outside or something..and then a few seconds later another explosion so it shook the building a little bit and so I went outside and that’s when I saw the fire,” said Jim Coelho, South Windsor.

No injuries have been reported at this time. The cause of the fire is also unknown.

Roads near the scene have been blocked off. Officials say Brainard Airport was shut down but has since reopened.

Fire officials are trying to keep the oil that didn’t burn from spreading. The Department of Energy and Environmental Protection is on scene. They’re using absorbent pads to contain it.