Oren Dorell

USA TODAY

Ambassador Christopher Stevens and three other Americans were killed

15 people in Benghazi who have tried to help the FBI probe have been killed

Questions remain about the role of military%2C Rep. Jason Chaffetz of Utah says

Congressional Democrats for the first time joined the GOP to condemn the State Department for refusing security measures they say could have prevented the deaths of the U.S. ambassador and three other Americans in Benghazi.

The report, worked on for months and released Wednesday by a bipartisan Senate intelligence committee, also says 15 people in Libya who have tried to help the FBI investigate the murders have been killed.

The report was prepared by the Senate Select Committee on Intelligence, and found that State, then under Hillary Clinton, refused requests to boost security despite warnings from the CIA and its own staff about the danger of militant attacks.

"The attacks were preventable, based on extensive intelligence reporting on the terrorist activity in Libya — to include prior threats and attacks against Western targets — and given the known security shortfalls at the U.S. Mission," the committee said in a statement.

Ambassador Christopher Stevens and three other Americans were killed in the Sept. 11, 2012, attacks after having made requests for more security to the State Department.

State has acknowledged that security was not adequate but has defended itself by saying that it never received intelligence indicating an attack of the ferocity of the terrorist assault. Numerous attackers were involved in the assault, which lasted several hours.

"We knew there were extremists and terrorists operating in Libya and in Benghazi," State Department spokeswoman Marie Harf said in response to the report. "But, again, we had no specific information indicating an attack was coming."

Rep. Jason Chaffetz of Utah, a Republican on the House Oversight Committee who has been investigating Benghazi, said the report is evidence that State kept security minimal to give an impression that U.S. policy in Libya was a success for the Obama administration.

"The bottom line is Hillary Clinton wanted the appearance of normalization" in Libya, Chaffetz said. "Security was not driving these decisions. Politics was."

Harf said that was "100% false."

The report did not discuss other questions of the attack, such as President Obama's role in responding to the attack. Also not discussed were allegations from State whistle-blowers that they were demoted for speaking against their superiors on the lack of security, or the question of what President Obama did the night of the attack.

The report, based on hearings and interviews with officials, government documents and survivors of the attack, did talk about efforts to save the Americans. It says that six CIA employees stationed at a previously undisclosed CIA station in Libya responded to the attack.

The report said the military response was slow and hindered but did not say it could have prevented the deaths. The Pentagon has been criticized by several Republican senators for not using all means to the aid of the Americans.

Documents show that the CIA was aware of the existence of Islamist training camps and militias in Benghazi, said the report, but did not make State fully aware of everything it knew.

U.S. officials involved in security at the consulate testified before a House committee last year that Stevens had informed his superiors of several incidents that concerned him greatly about the need for improved security. The CIA has also said it had made its concerns about security known to the White House.

Among the incidents leading up to the attacks were assaults on the Red Cross and British embassy personnel, and local militia charged with protecting U.S. staff acting in suspicious manners.

Yet the requests for a boost in security were denied by State.

In a House report released in April on Benghazi, Republicans say Clinton personally signed off on cuts in security at the compound.

The April cable from State acknowledged then-Ambassador Gene Cretz's formal request for additional security but still ordered "the withdrawal of security elements to proceed as planned," the Republicans said.

State Department cables, or internal messages, often are sent with the secretary of State's signature. The report did not say whether the cable regarding security was personally signed or drafted by Clinton.

Clinton appointed an Accountability Review Board to look into the attack and it faulted a "lack of proactive senior leadership" for security in Benghazi, and said physical security was "profoundly weak."

In testimony before Congress in January 2013, Clinton said that diplomats "accept a level of risk" in taking posts in dangerous areas and that they "cannot work in bunkers and do their jobs."

But she said it was State's responsibility to make sure diplomats have the resources they need to reduce the risks. Clinton called the attack "one of those terrible tragic times" when the State Department's security assessment of the situation failed.

"We are constantly assessing. And sometimes we get it wrong, but it's very — it's rare that we get it wrong," Clinton said.

In a letter to Sen. Rand Paul, R-Ky., she said the Accountability Review Board "made very clear" that the level of responsibility for the failures outlined in the cable was set at the assistant secretary level and below.

Sen. Susan Collins, R-Maine, a member of the Senate Intelligence Committee who issued an earlier report on Benghazi in December 2012, called the newest report a missed opportunity to call officials at State to account.

"Sufficient time had elapsed for the State Department to demonstrate whether or not decision makers would be held accountable for poor judgments, refusal to tighten security, and misinformation," Collins wrote.

Chaffetz said significant questions remain about the lack of military response to the attack, which went on for several hours after the Pentagon and the White House were aware it had begun.

"You'd think that would get people out of bed — let's get some planes ready — but apparently not," he said.

Regarding the 15 people killed since Benghazi, the report stated that it is not certain all the deaths were connected to cooperation with the United States.