Justice Department Inspector General Michael E. Horowtiz. (Drew Angerer/Getty Images)

The Justice Department inspector general anticipates making public on June 14 his report reviewing how the FBI and the department handled the investigation into Hillary Clinton’s use of a private email server, according to a letter sent to lawmakers Thursday.

In the letter to Republican and Democratic leaders on the Senate Judiciary Committee, Inspector General Michael E. Horowitz wrote that he was done with “much of” the review and classification of the report, and that he expected to make it public in a week’s time. Horowitz also agreed to testify before the committee on June 18.

Horowitz’s report is expected to blast former FBI director James B. Comey and other top bureau and Justice Department officials for the handling of the case, people familiar with it said. It will almost certainly be used by President Trump to attack current and former law enforcement leaders at whom he has repeatedly taken aim in recent days and months.

Trump this week questioned on Twitter whether Horowitz, who had previously hoped to finish the report in May, might be softening his findings. The inspector general wrote in his letter that he was completing the “ordinary processes” for such reports. As in all cases, those targeted by the report have been given a chance to review drafts of the findings and provide feedback, people familiar with the matter have said.

“What is taking so long with the Inspector General’s Report on Crooked Hillary and Slippery James Comey,” Trump wrote. “Numerous delays. Hope Report is not being changed and made weaker! There are so many horrible things to tell, the public has the right to know. Transparency!”

People familiar with the report said it takes particular aim at Comey, whose decisions at the end of the Clinton email investigation already have drawn significant criticism.

Comey, without telling his Justice Department bosses what he was about to do, announced publicly in July 2016 that he was recommending the case be closed with no charges. Then, just weeks before the election, Comey revealed to Congress that investigators had resumed their work — apparently bucking Justice Department procedure of not taking overt steps in a case that might have an impact in an election.

Clinton has blamed the move for her loss to Trump. Comey has defended his actions as necessary to preserve the integrity of the FBI in an unprecedented case.

June 14 is Trump’s birthday.