The suspected killer of a man who claimed he was wrongly beaten by police officers was nabbed over the weekend, police said.

Khalil Henderson, 23, was arrested on April 22 after highway patrol officers stopped a car he was in near Roosevelt Boulevard and Fox Street, said a police spokeswoman. 

Henderson was wanted for the fatal shooting of Najee Rivera, 23, at Somerset and C streets in December, while Rivera was intervening in an argument between women on the street. Rivera died two weeks after being shot.

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"I feel relieved," said Dina Scannapieco, Rivera's former girlfriend — who said that Monday was also her and Rivera's five-year anniversary. 

"That was great news to find out he was arrested," she said.

"He got pulled over and got caught with a gun," she said -— a 9 mm, she said, which is the same type of gun that killed Rivera.

Scannapieco said Henderson had even used a fake Facebook account to send her more threatening messages.

"He messaged me and said, 'I'm gonna kill your daughter next,'" she said.

RELATED: Man beaten by cops: ‘Give me my job back’ 

Rivera died after he interfered with a fight between two women he didn't know — one of whom was Henderson's girlfriend, according to Scannapieco. 

When Rivera saw Henderson strike his girlfriend, Rivera said, "You didn't need to hit a female like that," according to Scannapieco — and Henderson turned around and shot him in the stomach, she said. That wound killed Rivera two weeks later.

"He was just in the wrong place at the wrong time," Scannapieco said. 

Rivera was thrown into the spotlight in February 2015 after his girlfriend dug up surveillance video showing him being pummeled by police officers who claimed Rivera had assaulted them in a May 2013 incident.

The video got assault charges against Rivera dropped and the two officers, Kevin Robinson and Sean McKnight, were charged with assault.

Rivera did not live long enough to testify in their trial or see them acquitted of all charges.

"This isn't over … we need to make sure this case is solid and he doesn't beat this," Scannapieco said.