Windsor firefighters were called to a massive fire at the former Windsor Raceway Wednesday morning.

Firefighters received a call around 4:45 a.m.

Flames fully engulfed the structure and thick smoke could be seen coming from the area.

"The whole building the whole structure was engaging in fire. The whole roof was on fire straight across so it was creating signifcant amounts of heat," says Andrea DeJong, Acting Deputy Fire Chief.

The building was in the process of being demolished before the fire broke out early Wednesday morning.

It is not clear what caused the fire.

It wasn't a typical fire.

When crews  first arrived on scene the flames were too large and too hot making it difficult to put out.

Fire officials say they had to take a defensive tactic in orfer to help put out the blaze.

"It was left to burn because it burns cleaner creates less smoke and at the end of the day the building is under demolition. There nothing to save. So we didn't want to put the fire fighters at risk in order at the end of the day save nothing," says DeJong.

Luckily, there were no injuries as a result.

Crews are still dealing with several hot spots as the investigation continues.

"It's an extremely dangerous work atmosphere. The decision will be made at a later time frame maybe towards tomorrow once we get a better gage on whether we'll actually be able to have an investigator come in or whether it's going to be declares too unsafe," adds DeJong.