Photo: The Canadian Press

Two people remain trapped in the debris after a multi-storey scaffold collapsed overnight at a paper mill in Quebec's Eastern Townships.

Sylvain Bricault, the manager of the Domtar mill in Windsor, Que., said another worker was injured in the collapse and was transported to hospital, but his life is not in danger.

The incident took place at around 1:35 a.m. Tuesday.

The mill's emergency team, ambulance services and provincial police are participating in the rescue operation, Bricault told reporters at a press conference Tuesday morning.

An investigation into the cause of the incident is also underway, he said

Bricault said the condition of the trapped workers remains unknown.

He said the trapped workers are not Domtar employees and work for a contracting company that was doing major work at the factory.

The incident took place in the pulping section of the mill and all work has stopped in that part of the mill.

Several other people were in and around the scaffolding when the collapse took place and were able to get out with assistance, Bricault said, adding that they received psychological treatment.

Other workers who were in the area also received psychological treatment, he said, adding that support will be offered to other workers and their families.