Al Qaeda's active plans to carry out an attack in the United States led to Sunday's decision to declare financial institutions in Washington, New York and Newark, N.J., on Orange Alert, government officials told FOX News on Wednesday. 

"There was at least one plot in motion," an official said.

Officials said there was enough activity in Al Qaeda (search) circles to indicate that some kind of plans were being set in motion, although they cannot pin any sort of definition on those plans.

The Al Qaeda plot is directed toward the financial sector, sources said. It was this information, combined with other intelligence — including the surveillance details of particular buildings — that led Sunday to the threat level change.

U.S. officials said this particular piece of the puzzle came from a captured Al Qaeda operative abroad.

Also, a U.S. intelligence official told FOX News that an Al Qaeda operative discussed with British officials the possibility of attacks 60 days before the November election, and that focus also was on financial institutions. The intelligence source said officials are still trying to determine the credibility of the operative and the claims.

Sixty days before the Nov. 2 election is Sept. 2, the day President Bush is expected to address the Republican National Convention at Madison Square Garden in New York.

A senior defense official earlier had told FOX News that the threat found on the laptop was not limited to the Prudential Building in Newark, N.J.; Citigroup and the New York Stock Exchange in New York; and the World Bank and International Monetary Fund in Washington.

The United Nations' headquarters, American Stock Exchange and NASDAQ -- the bulk of whose operations are in Times Square, far uptown from the Financial District — were also named, FOX News learned, as were Morgan Stanley, Lehman Bros., Goldman Sachs, the Federal Reserve Bank, Bear Stearns, AIG, MetLife and JP Morgan Chase.

Law enforcement sources said that additional information obtained as recently as late last week justified raising the alert in the limited way it was raised. These sources said this intelligence — obtained from the new Al Qaeda capture — corroborated the information on the computer of Mohammad Naeem Noor Khan (search) and other intelligence gathered from ongoing interrogations and communications intercepts.

Khan is an Al Qaeda suspect and computer expert who was arrested in Pakistan on July 13. Information provided by Khan led to the arrest in eastern Gujrat on July 25 of Ahmed Khalfan Ghailani (search), a Tanzanian Al Qaeda suspect wanted in the United States for the 1998 twin East Africa embassy bombings. Ghailani also gave up some surveillance information and other potential terror information.

Most of the information on Khan's computer was amassed in 2000 and 2001. Officials have previously emphasized that the plot was more along the lines of operational planning, not a finalized, planned attack.

One source said Wednesday, however, that the most recent new information found by U.S. officials indicated the surveillance data was known and of interest to Al Qaeda operatives with experience planning attacks.

Multiple sources from defense and intelligence corners confirmed to FOX News that several "streams of intelligence" intersected to bring about the heightened security alert, including the laptop information and intelligence from other places.

Intelligence that became available on Friday and was pointed out in Wednesday morning's White House press briefing was "married up" with information obtained earlier, and the resulting picture was dire enough to prompt a series of meetings that, in turn, led to the orange alert.

"There's another new stream of intelligence that came to our attention on Friday as well, and I can't go further into it because I could compromise some ongoing operations," White House spokesman Scott McClellan told reporters.

A senior Justice Department official told The Associated Press that the information was based on human intelligence from someone other than two recently captured terror suspects in Pakistan who provided information that led to the warning issued Sunday. The intelligence did not specify when such an attack might be planned, the official said.

A senior counterterrorism official also told The Associated Press that the extensive surveillance reports that came to U.S. authorities last week were put together with "very recent and current activity" from Al Qaeda, indicating the group's interest in attacking this year.

"This is an enemy that takes its time and is a prodigious planner, that is very patient," Homeland Security Secretary Tom Ridge said Wednesday.

Ridge said on July 8 that there were Al Qaeda operatives in the United States and they were believed to have been working on something.

Meanwhile, it's been discovered that Khan made electronic contact with Al Qaeda operatives inside the United States. U.S. officials said they're still looking into it, and while they can't confirm at this point, they are not steering people away from the developing information.

FOX News' Bret Baier, Catherine Herridge, Ian McCaleb and Anna Stolley contributed to this report.