Attorney General William P. Barr personally told President Trump this week about an investigation into nine discarded mail ballots in northeastern Pennsylvania that the president later touted as evidence of widespread election fraud, according to a person familiar with the conversation, who spoke on the condition of anonymity to describe internal administration discussions.

The conversation came as Trump has fixated on the subject of voter fraud with aides, administration officials said, asking for information on the topic and updates from his campaign advisers and legal team about voting lawsuits. He has repeatedly lambasted voting by mail as susceptible to widespread fraud, despite evidence to the contrary.

The Justice Department made a public announcement about the Pennsylvania case Thursday after the president discussed it in a radio interview. The statement drew sharp criticism from voting-law experts, who questioned the timing and the details released, such as the fact that most of the ballots were cast for Trump.

Barr himself has echoed the president’s attacks on mail voting and leveled false assertions about the risks of mail ballots. He has suggested without evidence that foreign governments could easily inject counterfeit ballots into the system or that postal workers delivering ballots are susceptible to bribery.

Since the Watergate era, attorneys general have notified presidents about criminal cases of national importance, while trying to avoid discussions that would involve the administration in specific investigations, particularly those involving political figures. ABC News first reported Barr’s conversation with Trump about the Pennsylvania case.

A Justice Department spokeswoman declined to comment. A senior White House official said Trump was not “briefed” on the Pennsylvania case, but did not respond to a request for comment on whether the subject came up in a discussion with Barr.

At issue are nine ballots that officials said were found in an election office trash can on Sept. 16 in Luzerne County, Pa., in the northeastern corner of the state. Luzerne County Manager David Pedri said in an interview Friday that the ballots were discarded by an independent contractor who has since been fired. All nine were military ballots mailed in from overseas, he said.

Pedri said the county elections director discovered the ballots in an office trash can and “immediately began an internal inquiry.”

Pedri also said he and other local officials were not aware that seven of the nine ballots had been cast for Trump until the statement Thursday by the U.S. attorney’s office released that information.

Trump’s touting of the case — and his request that aides inform him of potential irregularities — alarmed election lawyers and voting-rights advocates, who emphasized that small mistakes happen every election year and do not prove the existence of widespread fraud.

“There’s a big difference between what happened in Luzerne County and systemic fraud that says you can’t trust the result of the election,” said Ben Ginsberg, a longtime election lawyer for Republicans.

Ginsberg said the Luzerne irregularities “absolutely” warrant investigation, but he also said officials need to distinguish between willful fraud and a simple mistake.

Trump first made an allusion to the Pennsylvania investigation Thursday in an appearance on Fox News Radio’s “The Brian Kilmeade Show” when asked about his refusal to commit to a peaceful transfer of power if he loses the election.

“I think we have a long way before we get there,” the president responded. “These ballots are a horror show. They found six ballots in an office yesterday in a garbage can. They were Trump ballots — eight ballots in an office yesterday in — but in a certain state and they were — they had Trump written on it, and they were thrown in a garbage can.”

White House press secretary Kayleigh McEnany then told reporters that there would be an announcement about the case. “I can confirm for you that Trump ballots, ballots for the president, were found in Pennsylvania, and I believe you should be getting more information on that shortly,” she said.

David J. Freed, the U.S. attorney for the Middle District of Pennsylvania, subsequently released a statement saying his office was investigating the discarded ballots, initially saying that all nine had been cast for Trump. He later clarified that seven of the ballots had been cast for the president and two were found sealed.

A spokesperson for the U.S. attorney declined to comment beyond Freed’s written statement or explain why he revealed the candidate for whom the votes had been cast.

Trump’s campaign pounced on the announcement. “Democrats are trying to steal the election,” one campaign spokesman wrote in a tweet, which went viral before he later deleted it.

The president also cited the case again in comments to reporters at the White House, saying, “We want to make sure that the election is honest, and I’m not sure that it can be.”

Two White House officials who spoke on the condition of anonymity to describe internal discussions said the White House decided to announce the investigation after Trump mentioned on the air and reporters began making inquiries.

Clifford Levine, a Democratic election lawyer from Pittsburgh, noted that Luzerne County voted for Trump by a 20-point margin in 2016, and county government is controlled by Republicans.

“It is the position of the Democratic Party that every legitimate vote should count, and we would not be satisfied if in fact a couple of votes were somehow inadvertently set aside. That would be inappropriate,” he said. “But there is no evidence of fraud or conspiracy.”

In a statement, Luzerne County said the contractor began work at the elections bureau on Sept. 14 and was assigned to sort mail. The discarded ballots were discovered two days later by the elections bureau director, and the contractor was removed, the county said.

“While the actions of this individual has cast a concern, the above statement shows that the system of checks and balances set forth in Pennsylvania elections works,” the statement said. “An error was made, a public servant discovered it and reported it to law enforcement.”

Pedri, the Luzerne County manager, said the matter was referred to the local prosecutor, who in turn called in the U.S. attorney. The FBI, state police and local prosecutors inspected all trash from the elections office for the three days the contractor was on the job.

Pedri declined to say why the contractor discarded the ballots or whether any further irregularities had been discovered beyond the nine ballots.

In a letter to the Luzerne County election office released Thursday night, Freed also said investigators recovered four “official, bar-coded, absentee ballot envelopes that were empty.” Those materials were discovered in an outside dumpster, he said.

“It was explained to investigators the envelopes used for official overseas, military, absentee and mail-in ballot requests are so similar, that the staff believed that adhering to the protocol of preserving envelopes unopened would cause them to miss such ballot requests,” Freed wrote. “Our interviews further revealed that this issue was a problem in the primary election — therefore a known issue — and that the problem has not been corrected.”

Asked if he was surprised that the investigation drew national attention, Pedri said: “Nothing surprises me anymore.”

“Obviously the investigation will uncover if there is any sort of a larger problem, and we’re happy to assist,” he said. “We are cooperating with that investigation. We are the ones who initiated it.”

Completed absentee ballots have only just begun to trickle into counties across the state; according to data provided by the Pennsylvania Department of State, fewer than 900 mailed ballots have been returned out of nearly 2 million requests processed so far.

Alice Crites contributed to this report.