Report: John Kelly and Corey Lewandowski once got into a fight that had to be broken up by the Secret Service

You may not need political experience to work in this White House, but a background in MMA could be helpful.

On Feb. 21, the same day families of Marjory Stoneman Douglas High School shooting victims were visiting with President Trump, White House Chief of Staff John Kelly and Corey Lewandowski, Trump's first campaign manager, got into a physical altercation, six people with knowledge of the scuffle told The New York Times on Monday. The fight took place outside the Oval Office, and Secret Service agents had to get involved after Kelly grabbed Lewandowski by the collar and attempted to push him up against a wall, people familiar with the incident told the Times.

It started when both men were meeting with Trump, and Kelly was critical of Lewandowski, saying he was making money off of Trump's name, the Times reports. Kelly was also unhappy with Lewandowski for going on television and discussing how he'd handled the situation with Rob Porter, the former White House staff secretary accused of domestic abuse by his two ex-wives. Lewandowski did not get physical, people with knowledge of the matter told the Times, and while he still visits the White House, aides make sure he doesn't go near Kelly.

Kelly, a retired four-star Marine Corps general, became chief of staff last year. Last week, it was reported he got into a screaming match with National Security Adviser John Bolton over immigration, and Anthony Scaramucci, the onetime White House communications director turned interpretive dancer, blasted Kelly on Sunday's Meet the Press, saying he "hurt the morale inside the place" and "has hissy fits." Read more about Kelly's temperament, and what his supporters have to say about it, at The New York Times.