Democratic Rep. Frederica Wilson shot back at President Trump moments after he claimed he has proof that she " totally fabricated" what he told the widow of a U.S. soldier who died in Niger.

"I don't know what kind of proof he could be talking about," Wilson said Wednesday on CNN. "I'm not the only person that was in the car. And I have proof too. This man is a sick man. He's cold-hearted and he feels no pity or sympathy for anyone."

Wilson said Tuesday that Trump told Army Sgt. La David Johnson's widow, Myeshia Johnson, that her husband "knew what he signed up for … but when it happens it hurts anyway."

Related: Trump told widow of fallen soldier her husband 'knew what he signed up for': Rep. Frederica Wilson

Trump says he has proof Wilson 'totally fabricated' his call with widow of soldier

Trump called Johnson shortly before her husband's body arrived at the Miami International airport. He was one of four soldiers killed in Niger this month.

Wilson said on CNN that Johnson told her Trump didn't even know her late husband's name.

"When she actually hung up the phone and she looked at me and said, ‘He didn't even know his name," Wilson said.

Related: Trump on calling families of fallen troops: 'Ask General Kelly' if Obama called when his son died