Fire ripped through an Oxford County barn on Monday killing about 100 cows.

Oxford County OPP responded to a fully engulfed barn fire at 544558 Clarke Road, South-West Oxford Township at about 2:05 a.m. Monday morning.

All South-West Oxford fire departments also attended the scene, along with Embro, Burgessville, Thamesford and Ingersoll fire crews assisting.

The residents of the property were all evacuated safely but the barn was levelled by the blaze.

A few cattle and a number of barn cats were rescued, but owner Clarence Markus says they could only watch with a sense of helplessness.

"The toughest part probably was you recognize what's happening and we left our house obviously because the buildings are fairly close to the house, but the toughest part was hearing these cows yelling and the agony they were going through was probably the toughest part of the whole thing."

The cause of the fire has not been determined and there is no estimate of the cost of the damage.

The OPP Criminal Investigation Unit will continue with the investigation. Clarke Road was closed between East Hill Line and West Hill Line, but is now open.

Police are crediting a trucker who notified the homeowners of the fire, preventing a potentially worse tragedy.

Oxford OPP Const. Lisa Narancsik says "Somebody was travelling on the 401 and saw the building engulfed in flames and proceeded to pull their vehicle over and hopped over the fence and banged on the door to notify the owners that the structure was on fire. So thank goodness for somebody who actually took it upon themselves to do that."