LUVERNE, Alabama, July 22 (Reuters) – A subsidiary of Hyundai Motor Co has used child labor at a plant that supplies parts for the Korean carmaker’s assembly line in nearby Montgomery, Alabama, according to area police, the family of three underage workers, and eight former and current employees of the factory.

Underage workers, in some cases as young as 12, have recently worked at a metal stamping plant operated by SMART Alabama LLC, these people said. SMART, listed by Hyundai in corporate filings as a majority-owned unit, supplies parts for some of the most popular cars and SUVs built by the automaker in Montgomery, its flagship U.S. assembly plant.

In a statement sent after Reuters first published its findings on Friday, Hyundai (005380.KS) said it “does not tolerate illegal employment practices at any Hyundai entity. We have policies and procedures in place that require compliance with all local, state and federal laws.” It didn’t answer detailed questions from Reuters about the findings.

SMART, in a separate statement, said it follows federal, state and local laws and “denies any allegation that it knowingly employed anyone who is ineligible for employment.” The company said it relies on temporary work agencies to fill jobs and expects “these agencies to follow the law in recruiting, hiring, and placing workers on its premises.”

SMART didn’t answer specific questions about the workers cited in this story or on-the-job scenes they and other people familiar with the factory described.

Reuters learned of underage workers at the Hyundai-owned supplier following the brief disappearance in February of a Guatemalan migrant child from her family’s home in Alabama.

The girl, who turns 14 this month, and her two brothers, aged 12 and 15, all worked at the plant earlier this year and weren’t going to school, according to people familiar with their employment. Their father, Pedro Tzi, confirmed these people’s account in an interview with Reuters.

Police in the Tzi family’s adopted hometown of Enterprise also told Reuters that the girl and her siblings had worked at SMART. The police, who helped locate the missing girl, at the time of their search identified her by name in a public alert.

Reuters is not using her name in this article because she is a minor.

The police force in Enterprise, about 45 miles from the plant in Luverne, doesn’t have jurisdiction to investigate possible labor-law violations at the factory. Instead, the force notified the state attorney general’s office after the incident, James Sanders, an Enterprise police detective, told Reuters.

Mike Lewis, a spokesperson at the Alabama attorney general’s office, declined to comment. It’s unclear whether the office or other investigators have contacted SMART or Hyundai about possible violations. On Friday, in response to Reuters’ reporting, a spokesperson for the Alabama Department of Labor said it would be coordinating with the U.S. Department of labor and other agencies to investigate.