Washington - Long-awaited testimony from Hillary Clinton on events leading to the deaths of four Americans in Libya in 2012 has revealed few new details, despite Republicans questioning the Democratic presidential contender for hours and Democrats slamming the investigation as a witch-hunt.

Following the marathon 11-hour hearing on Thursday, Clinton remained relatively unscathed after parrying away a seemingly endless barrage of questions about the attack on the US consulate in the Libyan city of Benghazi that killed US Ambassador Christopher Stevens and three others.

The question of whether the deaths could have been prevented remains one of the hotly contested issues on Capitol Hill.

Clinton, who was secretary of state at the time of the attack, was speaking for the second time before a Congressional committee to put to rest any lingering questions.

Speaking before a panel of 12 House members - seven Republicans and five Democrats - Clinton again said she bore responsibility for the tragedy, but rejected Republican attempts to blame the Benghazi attack on poor security precautions at the two facilities where the four Americans died.

"I take responsibility for what happened in Benghazi," Clinton told the committee, which is expected publish a final report on the incident in 2016.

But "I was not going to second-guess" the security professionals who made decisions on what to do in Libya prior to the attacks, she added.

She firmly rebutted claims that she failed to boost security at the US diplomatic compound overrun by fighters on September 11, 2012, saying she was never consulted directly about requests for additional measures.

'Legally accountable'

Some observers, however, believe Clinton bears more responsibility.

"She was legally accountable for personally issuing waivers in the Benghazi situation, where there was not a 100-foot (30-metre) setback and where all agencies (State Department and CIA) were not located in the same compound," said Diane Roark, a whistle-blower who served on the House Intelligence Committee from 1985 to 2002.

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The House select committee was set up to investigate what led to the Americans' deaths in Libya, and Clinton has now appeared twice to speak to her handling of the incident.

In almost two years, the committee interviewed more than 50 people, reviewed 70,000 pages of documents and held several public hearings. But many Democrats argue that this is a witch-hunt aimed at undermining Clinton's presidential bid.

Elijah Cummings, a Democratic Congressman, said the Republican-led committee had no rules or deadlines and an unlimited budget to sabotage Clinton's campaign.

"Republicans are squandering millions of taxpayer dollars on this abusive effort to derail Secretary Clinton's presidential ambitions," he said, calling for an end to a 17-month $4.7 million "fishing expedition".

Even some Republicans have questioned the committee's intentions: A Republican representative from California, Kevin McCarthy, was forced to drop from the speaker’s race after suggesting the purpose of the committee was to hurt Clinton's poll numbers

There have been seven Congressional probes into the attack on the US compound in Libya since 2012, but few new findings. What was uncovered by the committee was that during her time as secretary of state, Clinton used a private server to send and receive classified emails, which violated federal guidelines .

Republicans on Thursday also questioned Clinton on President Barack Obama's administration's Libya policy at the time, which led to Libyan leader Muammar Gaddafi's demise, and ultimately helped leave a power vacuum that led to a civil war and Islamist groups establishing a foothold in Libya.

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Some observers, who noted that Obama was the one who decided to join military intervention in Libya, said Republicans wanted to use her role in formulating US policy in Libya as evidence of her poor judgement there and in international affairs.

"Some Republicans are hoping that the more scandal you can have on Hillary, the more it diminishes her standing overall," said Jason Johnson, professor of political science and communication at Hiram College, Ohio.

"They have interviewed people on the ground and they have nothing new. It's not like new information has been acquired with these investigations. The purpose is to have people not trust her."

Source: Al Jazeera