HOUSTON (Reuters) - Marathon Petroleum Corp MPC.N, the largest U.S. oil refiner, began cutting jobs on Tuesday across the company, according to people familiar with the matter, as the COVID-19 pandemic sapped demand for motor fuels. U.S. refiners have posted large losses this year as fuel consumption tumbled amid lockdowns and work-from-home policies to combat the spread of the coronavirus. Thin profit margins have been undercut by the need to operate plants at less than 80% capacity. Marathon officials are “communicating with our employees about measures we announced earlier this year to strengthen Marathon Petroleum for short-term and long-term success,” a spokeswoman said in a statement. She declined to comment on specific actions. The Findlay, Ohio-based company has been shedding units to improve results. It had 60,000 employees as of Dec. 31, with two-thirds in retail operations that are being acquired by 7-Eleven Inc, an arm of Japan"s Seven & i Holdings Co Ltd 3382.T. About 60 salaried staff were let go by midday on Tuesday at Marathon’s large Galveston Bay plant in Texas and another 60 people were dismissed at the company’s Los Angeles refinery, the sources said. The Galveston Bay operation may lose as many as 100 workers this week and up to 200 before the reductions end, one of the people said. As of Tuesday night, 45 salaried employees had been let go at the Garyville, Louisiana, refinery, sources said. In August, Marathon began closing refineries in Martinez, California, and Gallup, New Mexico, eliminating 800 jobs. The latest cuts are across the company, one of the people said. It is expected to report a $623 million third-quarter loss on Nov. 2, according to IBES data from Refinitiv. It lost $9.2 billion in the first half of the year, mostly on impairment charges. Last week, LyondellBasell Industries LYB.N also disclosed plans to cut 10% of staff at its Houston oil refinery because of heavy losses. Plant operations would be challenged for several years because of the drop in demand, a LyondellBasell executive said.