A Homeland Security deportation officer arrested a migrant to try to deport him to prevent exposure of a $10 million bank fraud scheme, federal prosecutors charged.

Henry Yau, a supervisory officer at U.S. Immigration and Customs Enforcement, also accessed secret government immigration files and gave or traded the information to friends, investigators said in charges unveiled last week.

They said he poked into at least 28 files he shouldn’t have been accessing and spread the information among a dozen recipients.

In one instance, he offered to make an immigration arrest of a target to help out a friend, and in another egregious case, he made the arrest and carried out a deportation, authorities said. A confederate, a former high-ranking official with the New York mayor’s office, wanted to prevent the man from ratting out the fraud.

And he repeatedly performed checks for friends to see if they had flags that would have blocked them from re-entering the U.S. after traveling abroad, according to court records.

“Among other things, Yau allegedly tipped off an individual who was being investigated by the FBI; disclosed sensitive and non-public information from immigration and law enforcement databases; and, most egregiously, offered to use his authority as an ICE officer to arrest specific people at the request of, and as favors to, his friends,” said Damien Williams, the U.S. attorney in Manhattan, who brought the charges.

ICE said it couldn’t comment on Mr. Yau’s case but issued a statement saying the agency “stresses integrity and ethical behavior, and the vast majority of ICE employees perform their duties with professionalism and honor.”

A magistrate judge granted Mr. Yau a $2 million personal recognizance bond, secured by a $1 million cash deposit.

He has a preliminary hearing scheduled for Dec. 23.

A lawyer for Mr. Yau didn’t respond to an inquiry for this story.

Court documents didn’t identify the person Mr. Yau is accused of arresting to prevent disruption of the bank fraud. Documents do say that Tommy Lin, a former senior official in the New York mayor’s office, asked Mr. Yau to make the arrest.

Mr. Lin has been indicted for his involvement. The indictment says he was paid $20,000 to get Mr. Yau to carry out the arrest, which was done because the target had been part of the fraud but became “disgruntled.”

The person was arrested on Oct. 28, 2020, and Mr. Yau sent Mr. Lin a photo of the arrest, FBI Special Agent Robiel Ande wrote in an affidavit justifying the criminal charges.

Agent Ande said Mr. Yau tried to cover his tracks, including telling one person with whom he shared immigration records, “Do not disseminate” and “I don’t like to leave records.”

Many of the alleged schemes involved people with connections to China — including several targets whom Mr. Yau ran through the restricted government databases.

In one exchange with a co-conspirator, identified as CC-2, Mr. Yau suggested the man would be safe if he tried to run to Hong Kong.

“It’s ok because China doesn’t have an extradition [treaty] with the US,” Mr. Yau wrote in a message detailed in the court documents.

In the case of the fabricated arrest, Mr. Yau’s confederates worried that the target would go to the police and unravel the bank fraud scheme.

“Is there any way to keep his mouth shut and deport him directly?” a co-conspirator, CC-5, said in a 2020 message on WeChat, a Chinese message app Mr. Yau and the others used.