The Labor Department is investigating Perdue Farms and Tyson Foods — two of the biggest poultry producers in the U.S. — after reports that migrant children as young as 13 have been working overnight shifts to clean the companies' plants.

The department told NPR that its Wage and Hour Division is looking into the matter and could not provide additional details.

The inquiry comes after The New York Times Magazine published last week a harrowing account of a 14-year-old boy, Marcos Cux, whose arm was nearly torn off while working at a Perdue slaughterhouse on the Eastern Shore of Virginia.

According to the Times, Cux was hired by one of Perdue's contractors tasked with cleaning operations. He and other middle and high school-aged children made up about a third of the overnight shifts at the plant — handling acid and pressure hoses to wash away blood and meat scraps from industrial machines.

Under federal law, those tasks are strictly off limits for anyone under 18 because of the inherent risks. Cux admitted to lying about his age to get the job but the Times reported that it was a open secret among workers at the facility. The same practices were happening at a nearby Tyson-run plant.

Perdue spokesperson Andrea Staub confirmed the company is aware of the federal investigation and said it plans to cooperate.

"We take the legal employment and safety of each individual working in our facilities very seriously and have strict, longstanding policies in place for Perdue associates to prevent minors from working hazardous jobs in violation of the law," Staub said in a statement.

She added that Perdue is also conducting a "third-party audit of child labor prevention and protection procedures" that includes its contractors.

Meanwhile, Tyson Foods said it was not aware of any investigation as of Monday afternoon and therefore declined to comment.

The federal inquiry comes about seven months after the Biden administration vowed to crack down on illegal child labor in the country. In February, the Labor Department imposed a $1.5 million fine on Packers Sanitation Services Inc., one of the country's largest cleaning services for meat plants, for hiring minors. At the time, the department did not pursue food corporations, including Tyson, that had benefited from underage labor.

According to data from the Labor Department, child labor violations have nearly quadrupled since a low point in 2015 — leading to more injuries and deaths on the job. In July, 16-year-old Duvan Robert Tomas Perez died after getting entangled in a machine he was cleaning at a Mar-Jac poultry plant in Mississippi. In 2020, 16-year-old Gustavo Ramirez was doing construction work on a hotel roof in Tennessee when he fell 160 feet and died.