VICTORIA -- Hundreds of forestry workers on Vancouver Island will remain out of work as two pulp and paper mills extend closures due to what their owner calls "an exceptional intersection of events."

RCMP cybercrime experts launched an investigation in February into a reported malware attack at mills owned by Paper Excellence in Port Alberni, Powell River and Crofton.

The company was already struggling with a lack of wood, forcing it to announce a temporary curtailment of operations at its mills in Powell River and Crofton, south of Nanaimo.

On Thursday, the company announced it was extending the closures at the Powell River and Crofton mills into mid-summer.

Paper Excellence says it will continue some core operations at its Port Alberni operation as opportunities permit. It will also conduct some intermittent manufacturing runs in Crofton, if possible.

"Over the past six months, an exceptional intersection of events has negatively impacted our operations, including: a material shortage of economic forest fibre on BC’s coast; a significant external malware attack which rendered our paper business enterprise systems inoperable for a period of time, and from which we continue to recover as we work to restore all affected operations; and COVID-19 which has materially impacted the supply chain for many of the paper products that we manufacture," the company said in a statement Thursday.

Paper Excellence, based in Richmond, says it is working with municipal, provincial and federal governments to find relief measures for the industry.

"The entire situation is expected to continue to be highly fluid and the timeline may be modified in the coming months," the company said.