The janitors who have been on strike alongside autoworkers at General Motors sites have reached a tentative agreement with Aramark, according to a source.

Details were not immediately available. Aramark employs the maintenance workers and contracts for work at the GM locations.

The 850 janitors had been working on a contract extension since March 2018 before they launched a strike on Sept. 15, a day before GM autoworkers went out.

Both groups are represented by the UAW, and it was seen as critical by union members that both reach agreement around the same time. The UAW reached a proposed tentative agreement with GM on Wednesday, and members of the UAW National GM Council on Thursday decided to recommend that members ratify the agreement.

UAW autoworkers, who were instructed by the union to cross the janitors' picket lines on Sept. 15, had expressed great reluctance to do so again. The janitors are on strike at Flint Assembly, Flint Engine Operations, Flint Metal Center; the Metal Center Parma, Ohio; and the Technical Center in Warren.

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The Free Press has previously reported that the janitors, who also do maintenance work, are paid $11-15.18 per hour.

The workers have described some of the work they do as dangerous, using extremely high-pressure water to clean equipment in the paint shop, for example.