The Co-op Refinery has begun using helicopters to move supplies over the Unifor picket line and says it will be moving employees that way soon.

Roughly 800 Unifor Local 594 employees at the refinery were locked out at 5:30 p.m. CST Thursday. In a news release sent that day, a refinery representative said employees were being locked out to ensure the facility's safe and reliable operation.

On Sunday, the Co-op Refinery Complex released a statement that they would be using helicopters to move people and supplies over the picket line.

In the release, the Refinery management said they have been respectful of union members' right to strike, but some members have been engaging in inappropriate and dangerous behaviour.

"CRC employees have been harassed, accosted and verbally abused when crossing picket lines, and we simply won't stand for that behaviour," the release said.

On Monday, a spokesperson for the refinery said the helicopter was only transporting supplies but that there were plans to move employees in the future.

The <a href="https://twitter.com/Unifor594?ref_src=twsrc%5Etfw">@Unifor594</a> picket lines are rock-solid. <a href="https://twitter.com/CoopRefinery?ref_src=twsrc%5Etfw">@CoopRefinery</a> is forced to pay top-dollar to fly in scabs by helicopter. <a href="https://twitter.com/hashtag/skpoli?src=hash&ref_src=twsrc%5Etfw">#skpoli</a> <a href="https://twitter.com/hashtag/canlab?src=hash&ref_src=twsrc%5Etfw">#canlab</a> <a href="https://t.co/pOEmG05UUR">pic.twitter.com/pOEmG05UUR</a> —@UniforTheUnion

The refinery release alleges that members on the picket line have held up shipments of food and attempted to block shipments of parts needed for the plant. As a result, the release said the Refinery has been using helicopters.

"We take our responsibility for the safety of our community and to western Canadians' fuel supply seriously," management said in a release. "Any threat to the well-being of our people, and to the operational integrity of the refinery, will not be tolerated."

Kevin Bittman, president of Unifor Local 594, which represents the locked out employees, said Monday he isn't aware of any inappropriate behaviour from workers on the picket lines.

"I was on the picket lines all weekend," he said. "We didn't see any violence; we don't condone any violence."

Unifor Local 594 president Kevin Bittman said he hasn't heard of any picketing Unifor employees harassing or abusing non-picketing employees. (Brian Rogers/CBC)

He said there are "hundreds" of security vans driving the perimeter of the facility and employees are monitored by security officials on a constant basis. If there was an incident, he said it would likely be dealt with immediately.

"We've been telling our members, 'Act like there's cameras on you 24/7,'" he said. "They're not stupid. They know that the best way to win this battle is to keep the picket lines up and violence just gets them taken down."

He said the refinery using the helicopters shows the picket lines are working.

"[Co-op is] not getting what they need ... to get past our picketers, so they're spending the members' money on helicopters," he said. "If I'm a Co-op member, I'd be asking why we're spending all this money flying supplies in?"

Co-op said the helicopters were always a part of its business plan — to be used as a contingency.

As a result, spokesperson Brad DeLorey said the helicopters aren't having an impact of the company's finances.