Updated

White House officials are optimistic that the recent arrests of suspected terrorists and the seizure of detailed surveillance of financial buildings has undermined plans to attack the United States.

And they suggested, in television talk shows Sunday, some of the potential plots uncovered in the past week may have been part of a broader effort to strike the country before the November election.

"I certainly think that by our actions now that we have disrupted it," Frances Fragos Townsend (search), President Bush's homeland security adviser, said on "Fox News Sunday." "The question is, have we disrupted all of it or a part of it? And we're working through an investigation to uncover that."

But Sen. Joseph Biden (search) of Delaware, ranking Democrat on the Senate Foreign Relations Committee (search), said that based on the information he'd seen, he believes the Bush administration may have overstated the immediacy of the threat of an attack.

"I have not seen any hard evidence that there was an active moment that was contemplated in the very near term," Biden said Monday on NBC's "Today" show. "If there was a smoking gun that said we know for certain that was going to occur, I didn't see it."

In cooperation with U.S. intelligence agencies, authorities in Pakistan and Britain have detained suspected Al Qaeda (search) operatives, while computer files uncovered in Pakistan contained surveillance information of five prominent financial sites in New York, Washington and Newark, N.J. The administration issued a terror alert based on that information.

Townsend said it is not clear how much has been uncovered about a potential plot around the presidential election. "This certainly looks like it was a piece of it," she told CBS' "Face the Nation."

Besides the financial sites, counterterrorism officials have said other places have been mentioned as possible targets. Asked whether they included the Capitol and members of Congress, Townsend replied: "Yes, in the past and as part of this continuing threat stream."

"We may see additional U.S. targets," she said. "It's hard to judge that now until we have a better sense of what we see out of Great Britain, Pakistan and this arrest over the weekend in the United Arab Emirates."

Included in information obtained on three laptop computers and 51 discs seized in a July 24 raid in Pakistan were details of how Al Qaeda operatives thought of using speed boats and divers to carry out attacks in New York harbor before the November election, Time magazine reported, quoted an unidentified U.S. law enforcement official.

The plotters also were considering the use of helicopters in some New York operations, Time said.

A senior Pakistani Al Qaeda operative who formerly ran one of the terror group's training camps in Afghanistan was arrested in the UAE and has been handed over to Pakistani officials.

Both Townsend and Bush's national security adviser, Condoleezza Rice (search), praised Pakistan's efforts.

"Three years ago, Pakistan was not a fighter in the war on terrorism," Rice said on NBC's "Meet the Press." "And here you have them able to take down terrorists and to provide information, which then could be shared."

Rice defended the administration's decision to issue the terror warnings and tighten security in the three cities even though some of the surveillance intelligence on which the government acted dated from four years ago. Some have questioned whether the warnings were politically motivated.

"The idea that you would somehow play politics with the security of the American people — that you would not go out and warn if you have casing reports on buildings that are highly specific," Rice said. "Are you really supposed to not tell?"

Townsend and Rice said the administration was concerned that terrorists will try to disrupt the Nov. 2 election.

"The American people are going to react very badly to any attempt to disrupt our electoral process, but I think that in some of their minds, this is a possibility and we've indeed picked up discussion of trying to do something in the pre-election period," Rice told CNN's "Late Edition."

To act quickly on recommendations from the commission that investigated the Sept. 11 attacks, House Democratic leader Nancy Pelosi of California has urged Speaker Dennis Hastert, R-Ill., to call a special session of Congress. Hastert said House committees are working on the recommendations, with hearings this week.

"I hope that, when we come back in September and October, we have the recommendations and we can move forward," he said. Legislation to overhaul intelligence agencies could pass this year, he added.

Pelosi has called House Democrats to a meeting Tuesday with commission members.