Congressional investigators have issued a subpoena demanding that former Clinton White House adviser Sidney Blumenthal testify next month before the U.S. House of Representatives committee investigating the 2012 attack in Benghazi, Reuters reported on Tuesday.
The subpoena, a copy of which was made available to the news agency, demands that Blumenthal appear before the House committee on June 3 to give a deposition.
The subpoena is dated Monday but carries a notation indicating an unnamed deputy marshal served it on Blumenthal's wife on Tuesday.
The copy of the subpoena contains no further details about the subject matter of the deposition, noted Reuters.
More than two years ago, a set of emails sent by Blumenthal to Hillary Clinton while she served as secretary of state were posted on the Internet by a hacker who called himself Guccifer. Blumenthal did not work for Clinton when she was secretary of state and sent those emails as a private individual, the report said.
The emails included detailed private intelligence reports on events in Libya sent to Blumenthal by Tyler Drumheller, a former senior CIA officer. Some of the emails were sent around the time of the Benghazi attacks on and discussed information Drumheller's sources gave him about the attack.
On Tuesday, The New York Times published a handful of emails showing that Clinton had passed on some of the private intelligence reports to aides and other State Department personnel.
The messages show that at least one of the private intelligence reports made its way to a recipient who appears to have been Christopher Stevens, the U.S. ambassador to Libya who was killed in the September 11, 2012, Benghazi attacks, according to Reuters.
The emails are part of a batch of around 300 messages related to Libya that the State Department turned over to Republican Representative Trey Gowdy's Benghazi committee earlier this year.
The emails were submitted after it was revealed that Clinton used a personal address during her entire four years as secretary of state.
The Federal Records Act requires that government officials retain all of their written correspondence. As well, under specific guidelines signed into law by President Barack Obama, government e-mail accounts are supposed to be used in any situation involving official business.
People familiar with the set of Clinton emails turned over by the State Department to Gowdy's committee said that the emails leaked to The New York Times were not a complete set of messages related to what Blumenthal sent Clinton.
Blumenthal is a former journalist who served in the Clinton White House as one of the most loyal defenders of both Hillary Clinton and her husband, former President Bill Clinton, noted Reuters.
Clinton and the Obama administration have been criticized over their handling of the attack at the Benghazi consulate, in which, in addition to Stevens, three others were killed.
Republicans allege security failings led up to the attack and have also claimed there was a possible cover-up over Al-Qaeda's role in the attack.
In a testimony in 2013, Clinton said she took responsibility for the September 11, 2012 attack and cited a "personal" commitment to improving security provisions for U.S. diplomatic missions overseas.
Texas Republican senator Ted Cruz has said he believes Clinton purposely prevented the public release of details pertaining to the attack.