The Justice Department reportedly closed its investigation into whether Obama administration officials improperly unmasked the identity of former White House national security adviser Michael Flynn.

According to The Washington Post, the investigation was recently closed without charging anyone involved or releasing a public report on the issue.

Early this year, Attorney General William Barr tapped John Bash, the U.S. attorney for the Western District of Texas, to head up the investigation.

It follows the release of a document showing that 39 officials in the Obama administration and other federal agencies requested Flynn’s intelligence reports.

The document featured top-ranking figures including former Vice President Joe Biden, then-FBI Director James Comey, former CIA Director John Brennan, and several others. 

This month, Bash announced that he resigned from the Justice Department, citing “a position in the private sector.” Barr appointed Gregg Sofer, a veteran Justice Department attorney, to replace him.

“This morning, I submitted my resignation to the President and the Attorney General, effective Friday. Last month I accepted a position in the private sector,” Bash wrote in a tweet. His social media account is now suspended. 

The “unmasking” requests occurred after conversations between Flynn, President Trump’s incoming national security adviser, and former Russian Ambassador Sergey Kysliak were monitored during the presidential transition.   

Flynn pleaded guilty during the special counsel’s probe into lying to the FBI about his conversation in December 2017. He filed a motion to withdraw his guilty plea on Jan. 29, and the Justice Department moved to drop the charges.

Though “unmasking” names on classified documents is a common practice, the motive behind Obama administration officials’ requests might have been “problematic,” said DOJ spokeswoman Kerri Kupec.

“Unmasking inherently isn’t wrong, but certainly, the frequency, the motivation, and the reasoning behind unmasking can be problematic, and when you’re looking at unmasking as part of a broader investigation—like [U.S. Attorney] John Durham’s investigation—looking specifically at who was unmasking whom, can add a lot to our understanding about motivation and big-picture events,” she said.

Durham, the U.S. attorney for Connecticut, is investigating the origins of the Trump-Russia probe, which began during the 2016 presidential campaign.

Barr had told top Republicans that Durham’s investigation would not be released before the election, reported Axios, which cited people familiar with it.

So far, Durham’s investigation has led to only one criminal case against a former FBI attorney who pleaded guilty to altering a government email about a former Trump campaign adviser who was a target of secret FBI surveillance. 

Last week, President Donald Trump told radio host Rush Limbaugh that Justice Department investigators had “plenty of time to do it. They’ve been looking at it for two years. The facts are on the table.”

“If Bill Barr actually made that statement, I would be very disappointed in him. I don’t know that he made that statement,” the president said.