A federal prosecutor in Minnesota who was investigating an Immigration and Customs Enforcement officer for possible civil rights crimes has been fired, four sources familiar with the matter told CBS News.

Assistant U.S. Attorney Matthew Evans was investigating ICE officer Christian Castro over the shooting of a Venezuelan immigrant earlier this year. The Justice Department ultimately charged Castro this week with making false statements about the incident, but the indictment remains sealed, CBS News has previously reported.

Earlier this week, ProPublica reported that Evans told attorneys for the man who was shot, Julio Cesar Sosa-Celis, and other victims to prepare for Castro to only be charged with making false statements, which would carry lesser penalties than criminal charges that he violated people’s constitutional rights under color of law.

ProPublica quoted directly from an email it said Evans had sent to the attorneys.

“This is being directed by the Main Justice and the US Attorney,” the email from Evans reportedly said. “I objected in the strongest possible terms and fought it as hard as I could. It wasn’t enough.” (CBS News has not obtained the email reviewed by ProPublica.)

Three sources told CBS News that Evans is under investigation by the Justice Department. Two sources said the investigation focuses on allegations of leaking.

CBS News has reached out to Evans for comment.

A federal grand jury returned a six-count indictment against Castro on Wednesday, multiple sources familiar with the matter told CBS News. He was taken into custody in Texas on Thursday and will make an initial court appearance Friday, a source said.

The case revolves around a January incident involving Castro and Sosa-Celis, who officials say is in the U.S. illegally, during the Trump administration’s immigration crackdown in the Minneapolis area.

After Sosa-Celis was shot in the leg, federal prosecutors charged him and one other man — Alfredo Alejandro Aljorna — with forcibly assaulting, resisting or impeding federal officers. But the federal government’s description of the leadup to the shooting has shifted, and ICE later accused its agents of lying about the incident. 

Initially, the Department of Homeland Security said Sosa-Celis fled a traffic stop on foot, and when an ICE agent tried to arrest him, two other men attacked the agent with a shovel and a broomstick. DHS said Sosa-Celis then broke free and started attacking the agent, too, leading the agent to fire a “defensive shot to defend his life.”

But an FBI affidavit filed in the criminal case against Sosa-Celis and Aljorna alleged Aljorna, not Sosa-Celis, was the one who fled a traffic stop, and said Sosa-Celis had initially struck the ICE agent with a broomstick while the agent tried to arrest Aljorna. The agent described it as a three-minute-long tussle, according to the affidavit.

Cellphone video shared by a Democratic state senator also showed a woman telling 911 her husband was chased by ICE agents before he reached his home, and was shot in front of his family. And a video later released by The New York Times showed the altercation involving Aljorna and Sosa-Celis lasted far less than three minutes.

A month after Aljorna and Sosa-Celis were charged, the Justice Department dropped the case and said “newly discovered evidence” was “materially inconsistent” with the allegations against them.

Todd Lyons, who led ICE at the time, said a review of video evidence showed two ICE officers had made “untruthful statements” in sworn testimony. He said the officers would be placed on administrative leave and could face prosecution.

Castro, the ICE agent who shot Sosa-Celis, was charged in May on state charges of assault and falsely reporting a crime, and was arrested in Texas. But Texas Gov. Greg Abbott refused to extradite him to Minnesota, prompting a legal battle that ended with a Texas jail releasing Castro last week.

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