New York CNN  —  A janitorial company has been fined $649,000 after an investigation found it hired minors for dangerous jobs cleaning slaughterhouses, the United States Department of Labor said Monday. Fayette Janitorial Service had employed at least 24 children, including those as young as 13, according to the DOL investigation. The minors had been working overnight shifts at two separate slaughter facilities, according to the DOL. Federal labor law bans children from certain jobs in slaughtering and meat packaging plants, including using or cleaning machinery, due to the hazardous conditions. In addition to paying the fine, Fayette must hire a third party to prevent instances of child labor and set up a way to report concerns that children are being employed. “The realization that the use of fraudulent identification documents had allowed individuals under the age of 18 to circumvent our policies and procedures required immediate action,” Fayette said in a statement sent to CNN, adding that “substantial investments in proprietary systems and technologies has closed the gap that allowed this situation to arise.” The company added that it has cooperated with the DOL, and that “our goal remains to ensure a safe and compliant work environment for all of our employees.” The remedies come after a federal court issued a temporary injunction against the company in response to a DOL request in February. Photo taken on Nov. 8, 2021 shows the office building of the U.S. Department of Labor in Washington D.C., the United States. Ting Shen/Xinhua News Agency/Getty Images Related article Janitorial company hired minors to clean slaughterhouses, US Labor Dept. says Children were found working at Seaboard Triumph Foods Plant in Sioux City, Iowa, and at a Perdue Farms poultry processing facility in Accomac, Virginia, according to the DOL. “Minors were used to clean dangerous kill floor equipment such as head splitters, jaw pullers, meat bandsaws, and neck clippers,” the Labor Department said in a Februrary news release describing the findings of its investigation. Perdue “terminated our contract with Fayette Janitorial Services prior to this court filing,” a company spokesperson told CNN in a February statement, adding, “underage labor has no place in our business or our industry,” the statement continued. Seaboard, a pork processor, could not immediately be reached for comment. The company said in February that it had ended all of its contracts with Fayette, according to the Sioux City Journal. Instances of illegal child labor have been growing in recent years, and other contractors have been fined over employing minors. Last year, Packers Sanitation Services paid $1.5 million in civil penalties for employing minors in hazardous occupations and having them working overnight shifts, according to a DOL investigation.