B.C.'s struggling forestry sector has been hit with another big blow — forestry giant Canfor announced Friday that it's closing three sawmills in the B.C. Interior indefinitely and laying off about 570 workers.

The Vavenby mill north of Kamloops, the Radium mill in southeastern B.C. and the Rustad mill in Prince George will shut down once existing log inventories are processed and finished products are shipped, the company said in a statement.

Canfor CEO Jim Shepard said the decision wasn't easy, but was made because of the unprecedented length and intensity of the lumber market downturn.

"Canfor must continue to restructure its production capabilities to match the demands of the market and ensure the needs of key customers continue to be met," said Shepard.

The shutdown represents 11 per cent of Canfor's total capacity, and combined with previous shutdowns, will leave the company running at approximately 50 per cent of total capacity, said the release.

In recent years B.C.'s forestry industry has been hit with widespread shutdowns and thousands of job losses brought on by falling prices for lumber and pulp.