WHITBY, Ont. - Unifor says workers at an autoparts supplier in Whitby, Ont. have walked off the job in solidarity with the union's campaign to save the General Motors assembly plant in Oshawa, Ont.

The union says employees at the Lear Corp. operation, which supplies seats to the GM Oshawa plant, started demonstrating early Friday morning.

It says the 350 workers at the Lear plant face probable job losses if GM goes ahead with its planned closure of the Oshawa plant by the end of the year.

Unifor president Jerry Dias says the workers and the union are demanding government action to help protect jobs.

The closure of the Oshawa plant will mean the loss of about 2,600 unionized jobs. The union says thousands of spin-off jobs are at risk because of the closure.

Unifor has been campaigning to save the plant, including with walk-offs and a call to boycott GM vehicles from Mexico, since the company announced its plans last November.