REGINA -- The Co-op Refinery said it is using helicopters to transport staff into the Regina facility as job action continues.

"Anything that can come into this plant to sustain it, they're not allowing any of that in,” Vice President of Refinery Operations at Federated Co-operative Limited Gil Le Dressay said. “They only thing that they are allowing in and out is fuel trucks, and the fuel trucks, they have curtailed our ability by about 50 per cent.”

An hour after issuing official strike notice, the refinery locked unionized employees out of work.

In a news release, the refinery said it's made the move to helicopters due to "inappropriate and dangerous behaviour by Unifor members on the picket line."

"Due to the dangerous situation at the picket lines and the need to ensure the safe operation of our refinery, we have brought in helicopters to transport our staff safely across the picket line," the refinery said in the release. It also said it is working to make sure it is moving fuel safely from the refinery to fuel stations across western Canada.

Co-op is now alleging that Unifor members have been making threatening and harassing remarks towards people trying to come in and out of the complex.

"People that are exposed, they're getting harassed.” Le Dressay said. “They're getting slurs attacks against them, you know you can imagine what those slurs are. Some of them have been threatened with violence those types of things have been towards the police for criminal investigation."

CTV News reached out to the Regina Police Service who said it’s aware of complaints and its gathering information but no arrests have been made.

Unifor 594 denies the harassment allegations by the refinery.

The union said it has been allowing fuel trucks to enter and exit the facility. Unifor told CTV News Regina some trucks have been delayed, but were allowed to go through shortly after.

"I haven’t seen any harassing or anything like that,” Unifor Local 59 President Kevin Bittman said. “It's a picket line and we got locked out of our plant so we're not going to let replacement workers go in there very easily to do our work and I think they should expect that. But you know I've seen nothing but respect on the picket lines so I’m not sure what they are talking about."

More than 700 union workers are impacted by the job action.