Sources: Trump likely to tap another retired general for DHS secretary

President-elect Donald Trump is reportedly circling in on tapping retired Marine Corps Gen. John Kelly to helm the Department of Homeland Security, adding to the list of generals already poised for leadership roles in the billionaire businessman's White House.

Should Kelly, 66, be formally offered the post, he will be the third general tapped by the president-elect. Trump chose Lt. Gen. Michael Flynn as his national security advisor and retired Gen. James Mattis, whom Trump said he will nominate for Defense secretary. In addition, Trump is considering retired Gen. David Petraeus for secretary of state.

Kelly's military background spans more than 40 years and, earlier this year, he retired from his post as chief of the U.S. Southern Command, where he oversaw military operations in most of South and Central America. The former Marine also served several tours of duty over his military career, according to Politico:

Kelly enlisted in the Marine Corps in 1970 and was discharged two years later. He was then commissioned as an officer in 1976. He served multiple tours of duty in Iraq and was a military aide to both Defense Secretaries Robert Gates and Leon Panetta.

He had a run-in with President Barack Obama's administration when it came to Guantanamo Bay, which the president worked unsuccessfully to close. Kelly said it was "foolishness" for there to be concerns about the military's treatment of detainees — and the U.S.'s moral standing — at the facility in Cuba.

Though Kelly supported Trump's plan to secure the border and crack down on illegal immigration, he suggested during the campaign that he would be willing to serve in either Trump or Democratic presidential candidate Hillary Clinton's administration.

He said neither candidate should doubt they would be "getting anything but the absolute best military advice, completely devoid of politics."

"It adds to this mistrust issue ... if suddenly a guy retires and says, 'I think this administration is doing all the wrong things for all the wrong reasons,'" he told Foreign Policy in July about endorsing a candidate.

Kelly's son, 2nd Lt. Robert M. Kelly, died in 2010 when he stepped on a landmine on a tour of duty in Afghanistan. To date, Kelly is one of the senior most U.S. military officials to lose a child in the War on Terror.