"Let me begin by asking you if you think Ambassador Stevens and the three other Americans died as a result of a terrorist attack," Sen. Joe Lieberman, I-Conn., asked Matthew Olsen, director of the National Counterterrorism Center.

"Yes, they were killed in the course of a terrorist attack on our embassy," Olsen replied.

It's an admission that has raised new questions.

"Was there actionable intelligence prior to this attack, and if there was not, why not?" Sen. Pat Roberts, R-Kan., asked.

President Obama and Secretary of State Hillary Clinton are now on the hot seat.

In the days following the attack on the consulate, the administration claimed it was the result of protests over an anti-Muslim film.

"It was a spontaneous, not premeditated. A response to what happened in Cairo," Susan Rice, ambassador to the United Nations, told ABC's "This Week" Sunday.

CBN News Terrorism Analyst Erick Stakelbeck immediately rejected that theory.

"I think this claim by the Obama administration, continued claim, flies not only in the face of fact, it's actually embarrassing," Stakelbeck said. "What I'm hearing here in D.C. is open laughter at these claims."

Republican leaders also spoke out against the claim.

"What happened in Benghazi was not an anti-American protest. It was not as a result of a YouTube video. It was an orchestrated, anti-American terrorist attack," Sen. Marco Rubio, R-Fla., said.

Now new information is surfacing that suggests the attack was pre-planned. A U.S. intelligence officer investigating the attack told the Daily Beast that the consulate was staked out and monitored ahead of time.

"It shows the level of, abysmal level of, their knowledge about fundamental aspects of terrorist attacks and militant operations," Sen. John McCain, R-Ariz., charged.

Meanwhile, U.S. Ambassador Chris Stevens and the three other Americans killed in the attack were honored in Tripoli Thursday.

"He was with the rebels since the beginning of the revolution," Libyan President Mohammed el-Megarif said at the service. "He gained the trust of the Libyan people."