The Labor Department found that one of the largest food safety companies in the United States illegally employed more than two dozen children in at least three meatpacking plants.

The injunction was filed against Packers Sanitation Services by the department. On Thursday, M. Gerrard quickly ordered. The injunction requires the company to stop using child labor and comply with a Labor Department investigation.

Packers provides contract work at hundreds of slaughtering and meat packing plants across the country.

The Labor Department found that Packers employed at least 31 children, ranging in age from 13 to 17, who cleaned dangerous equipment with corrosive cleaners during overnight shifts at three slaughtering and meat packing facilities.

They worked on kill floors, meat- and bone-cutting saws, grinding machines and electric knives. The mix of boys and girls did not speak English very well.

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According to the Labor Department, several minor employees suffered caustic chemical burns and other injuries. A 14-year-old was injured from cleaning machines that cut meat. The student fell asleep in class because of the job at the plant, according to school records.

The Labor Department believes Packers may use minor children at other plants.

The company was accused by the Labor Department of interfering with the investigation by intimidating minor workers to discourage them from cooperating.

Packers has an absolute company-wide prohibition against the employment of anyone under the age of 18 and no tolerance for any violation of that policy. The company was accused of not cooperating with the investigation.

Turkey Valley farms said that it was taking the allegations very seriously and that it was reviewing the matter internally.

The company said it expects all contractors to share their commitment to the health and safety of any individuals working in their facilities and to adhere to these principles that foster a safe work environment. Based on the outcome of the Labor Department's investigation, it will take all appropriate action.

A request for comment from the company was not responded to on Friday.

The Labor Department's Wage and Hour Division in Chicago said that federal laws were established decades ago to prevent employers from profiting by putting children in harm's way. Packers Sanitation Services Inc.'s disregard for the law and for the well-being of young workers is demonstrated when they take advantage of children and expose them to workplace dangers.

Children under the age of 14 are not allowed to work during the summer and the school year. They are not allowed to work more than three hours on school days and more than eight hours on non-school days. Minors can't operate dangerous equipment.

Packers was being investigated by the Labor Department after it received a referral that the company was assigning hazardous work to children. The department said they conducted interviews with many minor children and conducted investigations into the company's operations.