The chairman of a congressional committee investigating the 2012 attack on a U.S. consulate in Benghazi, Libya, said "huge gaps" exist in the emails Hillary Clinton has turned over to the panel, Reuters reported.

The then-secretary of state was famously photographed gripping her BlackBerry as she flew to the North African country in the aftermath of the incident, the New York Post recalled. But Republican Rep. Trey Gowdy, who heads the House select committee on Benghazi, said no emails from the trip were released.

"It strains credibility to believe that if you're on your way to Libya to discuss Libyan policy, that there's not a single document that's been turned over to Congress," the congressman from South Carolina argued. Gowdy last week issued subpoenas for Clinton's Libya-related emails.

Clinton, who is considered the Democratic frontrunner in the 2016 White House race even though she has not officially declared her candidacy, came under fire last week when it was revealed she had exclusively used her private email account to conduct government business during her time as the nation's top diplomat.

Her advisers had to sift through tens of thousands of pages of personal messages and decide which ones to turn over to help the State Department comply with federal record-keeping practices, the New York Times had noted; in the end, some 55,000 pages were submitted.

President Barack Obama, meanwhile, said on Saturday he only recently learned of Clinton's communications practices.

Anticipating her presidential run, Republicans have scrutinized Clinton's response to the Benghazi attack, which resulted in the death of then-Ambassador Chris Stevens and three other people, Reuters reported. Gowdy said though his committee has received 800 pages of emails, it should not be up to Clinton to decide which of her messages were to be made public.

The chairman said he had "lost confidence in the State Department," CBS noted, adding Americans deserve a "neutral, detached arbiter" to decide what is a matter of public record.

"They're the ones who allowed this arrangement," Gowdy said. "They're the ones who did nothing about this arrangement until they got a request from our committee."