WASHINGTON (Reuters) - A long-awaited U.S. Justice Department internal watchdog report on former FBI chief James Comey’s public disclosures on Hillary Clinton’s use of a private email server while secretary of state and whether FBI employees leaked information to try to hurt her 2016 presidential bid is expected to be issued next month.

Former Secretary of State Hillary Clinton speaks at the annual Hillary Rodham Clinton awards ceremony at Georgetown University in Washington, U.S., February 5, 2018. REUTERS/Aaron P. Bernstein

The report from Michael Horowitz, the department’s inspector general, arises from an investigation he launched about a week before Republican President Donald Trump, who defeated Democrat Clinton in the election, took office in January 2017.

In a letter last week to Republican Representative Trey Gowdy, chairman of the House of Representatives Oversight and Government Reform Committee, Horowitz said his office was “working diligently” to complete the report and expected to release it in May.

Horowitz’s letter did not offer details of what will be in the report. In a Jan. 12, 2017 letter to five congressional committees, he enumerated 2016 election-related issues his office would look into.

Clinton has called the FBI investigation into her emails and Comey’s public disclosures about it significant factors in her loss to Trump, who fired Comey as FBI director in May 2017.

The investigation will examine Comey’s statements in August 2016 that no charges would be brought against Clinton and in October about the re-opening of the FBI investigation into her use of a private email server rather than a government server, potentially jeopardizing classified information.

The report also is expected to address whether active and retired FBI agents in New York leaked information about investigations of the Clinton Foundation charitable organization and the discovery of a trove of Clinton-related emails.

Law enforcement officials previously told Reuters the information was leaked to former New York Mayor Rudy Giuliani, an adviser to the Trump campaign who subsequently discussed the contents on Fox News.

Horowitz’s office also has sought to determine whether such leaks influenced Comey’s decision 11 days before the election to announce the reopening of the Clinton email investigation. Law enforcement sources with knowledge of the matter, speaking on condition of anonymity, said at the time a fear of leaks from within his own agency helped prompt Comey to make that public disclosure.

Comey did not respond to a request for comment.

Trump and Comey have exchanged harsh criticism in the past week. Trump called Comey a “slime ball.” Comey called Trump an unethical liar who is morally unfit to be president.