Former White House chief of staff John Kelly has joined the board of directors of a company that operates four shelters for illegal migrant children in America's southwest.

CBS News reported that Kelly is a member of Caliburn International's board. The retired Marine Corps general previously served on the board of a company that now owns Caliburn before joining the Trump administration.

"With four decades of military and humanitarian leadership, in-depth understanding of international affairs and knowledge of current economic drivers around the world, General Kelly is a strong strategic addition to our team," Caliburn CEO James Van Dusen said.

Caliburn owns Comprehensive Health Services, the company that operates the shelters. According to CBS, the federal government paid Comprehensive at least $222 million to operate one of the shelters from July 7, 2018 to April 20, 2019.

Kelly served as secretary of Homeland Security in the first half of 2017 before President Donald Trump moved him to the position of White House chief of staff. He departed at the beginning of 2019.

Unaccompanied migrant minors are being temporarily kept in facilities along the southern border as the Trump administration grapples with the illegal immigration problem.