On a busy first day back to classes, University of Windsor students were greeted by picket lines.

About 300 members of the Canadian Union of Public Employees Local 1393, who work at the university, went on strike Sunday.

U of W president Alan Wildeman says classes won't be cancelled, but some faculty may choose not to cross picket lines.

President of CUPE 1393 says about six professors have said they won't cross picket lines. If that happens, those classes would be cancelled

The local represents 280 skilled trades and professional staff, including equipment technicians, carpenters and graphic designers. Workers have been without a contract since April.

The employees were in a legal strike position as of midnight Sunday.

Through a provincially-appointed mediator, CUPE says it will be requesting further meetings with the university.