For the second time in a week, a group of support staff at the Voisey's Bay nickel mine in northern Labrador has walked off the job.

About 60 employees of the contracting company Ushitau Maintenance launched picket lines Monday morning.

Last week, employees with Torngait Services went on strike.

Both groups of workers are seeking the same quarterly bonuses paid to direct employees of Voisey's Bay Nickel. The bonuses are worth as much as $30,000 per year.

The contracting companies provide a range of services ranging from snowclearing to housekeeping.

Managers are performing those duties. After the Torngait strike began, Voisey's Bay Nickel said it did not anticipate significant problems with production.

In addition to one of the world's largest nickel finds, Voisey's Bay contains commercial discoveries of cobalt and copper. The mine began exporting concentrate in late 2005.