Fire officials say a medical growop being erected inside a Prest Road barn didn't cause the fire that led to the structure's destruction and the death of six sheep late Saturday night.

But it took fire crews seven hours to extinguish a fire in the barn, in the 6600 block of Prest Road, because of the grow-op-related renovations, according to assistant fire chief Ian Josephson.

The blaze broke out at around 8 p.m. Saturday night.

The front of the barn housed about 30 sheep and featured several heat lamps meant to keep the livestock warm. The back of the barn was being outfitted to house a medicinal marijuana grow operation, according to Josephson. Workers had spent three months on the renovations and were finally nearing completion.

No specific cause has been determined.

"It was an accidental fire for sure," said Josephson. He speculated that the heat lamps could be to blame, although the farmer who uses the space told investigators that the lamps were not turned on when he last left the barn. Fire officials did confirm that the blaze originated in the portion of the barn being used to house the sheep, then spread to the part of the structure being renovated for the marijuana grow.

The grow-op-related renovations- including walls reinforced with steel rebar-caused firefighters difficulty in attempting to extinguish the blaze.

"It wasn't something we were expecting," he said.

No marijuana was in the barn at the time of the fire. The RCMP continues to investigate.

tolsen@chilliwacktimes.com