WASHINGTON -- A senior House Republican on Monday escalated the GOP's battle with the FBI over its decision not to recommend criminal charges against Hillary Clinton for her use of a private email system, serving a top FBI official with a subpoena for the investigation's full case file.

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The move during a congressional hearing by Rep. Jason Chaffetz, R-Utah, the chairman of the House Committee on Oversight and Government Reform, underscores mounting frustration within the GOP over what Republicans see as stonewalling by the FBI over the Clinton probe. Chaffetz and other Republicans on the panel said the bureau has withheld summaries of interviews with witnesses and unnecessarily blacked out material from documents sent last month.

"We decide what's relevant -- not the Department of Justice, not the FBI," Chaffetz said. "We are entitled to the full file."

Democrats insist the sole purpose of the hearings is to undermine Clinton's bid for the presidency.

Dismissing the "emergency" hearing late on a Monday, Rep. Elijah Cummings, D-Md., said, "As far as I can tell, the only 'emergency' is that the election is less than two months away."

Chaffetz issued the subpoena to Jason Herring, the acting assistant director for congressional affairs at the FBI. Herring and six other Obama administration officials appeared before the committee to discuss the investigative files. The witnesses on several occasions said they could not answer the questions from lawmakers in an open forum.

The committee later voted to hold the remainder of the hearing in closed session.

FBI Director James Comey last week defended the decision to forgo criminal charges against Clinton after a lengthy probe into whether then-Secretary of State Clinton mishandled classified information that flowed through the private email system located in her New York home. Comey told bureau employees in an internal memo that it wasn't a close call.

Republicans have assailed Comey's decision and demanded that the Justice Department open a new investigation into whether Clinton lied during testimony last year before the House panel investigating the deadly 2012 attacks in Benghazi, Libya. Democrats have countered by accusing GOP lawmakers of using their congressional authority to advance a partisan agenda and undermine Clinton's candidacy for president.

The FBI provided parts of the Clinton probe file to Congress last month and warned lawmakers that the documents "contain classified and other sensitive material" and are not to be made public. Republicans have said the documents "did not constitute a complete investigative file," as many of the records had been substantially blacked out or were missing altogether.

In addition to Herring, officials from the congressional and legislative affairs offices at the Justice and State departments, office of the Director of National Intelligence, CIA, National Security Agency and National Geospatial-Intelligence Agency appeared before the committee.

Comey announced in July that he had recommended against criminal charges for Clinton. Although he described her actions as "extremely careless," he said investigators found no evidence of criminal wrongdoing.

In the memo to FBI staff last week, Comey said the case was "not a cliff-hanger; despite all the chest-beating by people no longer in government, there really wasn't a prosecutable case," Comey wrote in an internal memo. "The hard part was whether to offer unprecedented transparency about our thinking."

A Section on 09/13/2016