Dean Foods is closing its milk-processing plant in Thief River Falls and is laying off 52 workers as a result.

The plant, which also processes milk for Land O’Lakes, will close by Oct. 15, according to a notice filed Tuesday by Minnesota Department of Employment and Economic Development. The company is laying off the employees in rounds. The first group of employees was let go last week. Layoffs will continue throughout the summer.

Some of the affected workers are represented by the Teamsters Local 120 union. Both union and nonunion workers are losing their jobs. Dean Foods, which is closing the plant permanently, could not be immediately reached for comment.