ROANOKE, Texas -- A hangar fire burned at Northwest Regional Airport in Roanoke, officials said Sunday.

Authorities said that the pilot of an incoming plane saw the flames and alerted the fire department, which found the hangar fully burning, leading fire officials to assign a second alarm to the hangar.

The hangar belonged to a man who kept several vehicles in it including two RVs, two race cars and three antique classic cars, officials said. There was some other equipment, but no planes inside the hangar.

Officials said that fire crews that were on scene were going to implement a defensive attack against the blaze.

Extra help was requested from 10 agencies, including Double Oak, Highland Village, Denton, Lewisville, Ponder, Argyle, Justin, Westlake and Flower Mound fire departments, officials said.

Authorities said there was no word of any injuries and the cause of the fire remained under investigation.

The estimates for losses were expected to be extremely costly, officials said.