The Antrim councillor - who was on his way home from work and witnessed the fire take hold of the former car showroom - said vandals had repeatedly targetted the disused premises over the last number of months.

"This could have been a lot more serious than it was," Cllr. Graham said.

He added: "If the wind had been blowing in a different direction, the fire could have spread to the adjacent nursing home and perish the thought if that had happened.

"There's gas and oil tanks at the adjacent buildings - it just doesn't bear thinking about."

Cllr. Graham - a postman in the borough - had been finishing his shift and was heading back to the postal depot at the Steeple Industrial Estate at around 4pm on Saturday.

There was no sign of the fire but as he left the depot to make his way home, he saw a puff of smoke coming from the unit.

"I was about to call the fire brigade when I heard sirens in the distance with the fire service arriving shortly after," Cllr. Graham said.

Nine fire appliances were called in to deal with the blaze with 45 fire-fighters battling to bring it under control.

The fire was reported to crews around 4pm and took four hours to be put out.

A significant section of the building has been destroyed in the fire.

The Parkhall councillor said the disused property had been targetted in the past, with windows being smashed, adding he was of the opinion that fire had been deliberately started.

Praising the fire service for their handling of the situation, Cllr. Graham voiced concerns over the police's presence at the scene of the fire.

"I stayed down at the fire for quite some time and it was about 40 to 50 minutes before any police turned up," Cllr. Graham said.

He added: "I've no issue of how they handled the situation when they arrived - they took control and helped get the traffic diverted away from the area; there is no issue in that respect, it's that they took so long to arrive that concerns me."

Cllr. Graham said it was his understanding that officers had been dealing with a car crash on the Moneynick Road in Randalstown and had been tied up on calls elsewhere in the borough.

"My concern is that there's not enough police for when a situation like this occurs," Cllr. Graham said.

He added: "It's my understanding that there are only two response crews on on a Saturday afternoon. Clearly that's not enough and although we're often told that resources can be drawn from neighbouring areas, it still means a lengthy wait for police to arrive.

"Police resources are only going to get worse once we lose the full-time reserves and I would be greatly opposed to moves to get rid of the full-time reserves."

Police are appealing for any witnesses to the fire to come forward to assist them with their enquiries.