Members of the Senate received a closed-door classified briefing today from the FBI, the NCTC, the CIA, State Department and Treasury on the Iranian terror plot divulged Tuesday.

Emerging from the nearly two-hour briefing , Senate Intelligence Committee Chairwoman Dianne Feinstein, D-Calif,  speculated that, “There may be a chain of these things. … It’s hard for me to believe that there is just one plot involving the United States. I think we need to explore whether there are other plots going on … in other countries.”

On Tuesday, it was revealed that FBI and DEA agents disrupted a plot to commit a “significant terrorist act in the United States” tied to Iran, federal officials told ABC News today.

The officials said the plot included the bomb assassination of the Saudi Arabian ambassador to the United States, Adel Al-Jubeir, and subsequent bomb attacks on the Saudi and Israeli embassies in Washington, D.C. Bombings of the Saudi and Israeli embassies in Buenos Aires, Argentina, were also discussed, according to the U.S. officials.

Today, Feinstein said that intelligence indicates that there “may well be problems elsewhere” that need to be looked at.

She speculated that the Quds force of Iran would not have launched such a plot without the highest levels of approval from the country’s Revolutionary Guard and mostly likely from some higher elements of the government. She said she did not know if Iranian President Mahmoud Ahmadinejad was involved.

“This is a very unusual thing,” she said. “And because it’s unusual, because it’s Quds force, because it’s Revolutionary Guard, two agencies very high in the hierarchy in the Iranian government, you’ve got to think if they’re going after a Saudi ambassador here, what about a Saudi ambassador there or an Israeli ambassador there, or an American ambassador. So I think we should all be alert to that. But I am not saying there is a broader plot.”

From what she heard in the briefing, Feinstein said, she thinks there are already various responses taking place from the U.S. administration, including diplomatically and through the Department of the Treasury.

“I think the administration has moved very rapidly,” Feinstein said.