The Department of Homeland Security (search) announced that the United States would stay in a heightened state of terror alert beyond the holiday season, but the country may in fact be ready to downgrade the alert level fairly soon, Fox News has learned.

"The level and volume of very credible threat reporting has gradually dropped off," a Homeland Security official told Fox News on Tuesday.

The official said the reduction in credible threat reporting began last weekend, and that if it continues key decision-makers will consider lowering the threat level. Returning to yellow, or "elevated," terror alert status would in turn mean a ratcheting down of protective measures around the country, the official told Fox News.

The official added that the current volume of overall threat information received by authorities has not declined, but explained that this was to be expected with more security personnel actively engaged and citizens more inclined to report information they believe may be significant.

Homeland Security officials had announced on Monday the country would stay in a high state of terror alert due to intelligence suggesting attacks may be planned.

The nation's alert status was boosted to orange — or "high" — on Dec. 21, based on intelligence regarding possible terror attacks during the holiday season.

And though the holidays have come and gone, officials said human intelligence, computerized watch lists and intercepted communications continue to suggest attacks may be planned.

"The threat information is evaluated on a daily basis," Homeland Security spokeswoman Rachel Sunbarger said. "At this time, the information we have warrants that we remain at a heightened state of alert."

"I think the country is justified in keeping the threat as long as we have any indication that something could happen," added Rep. Martin Frost, D-Texas.

White House spokesman Scott McClellan said it's hard to say whether terrorist incidents were disrupted since the alert level was raised. But, he added, when the alert has been elevated in the past, it has served as a deterrent to attacks.

"The information that was the basis for raising the threat level to begin with still remains — I think we can expect that this heightened level will be with us for a few more weeks," Rep. Chris Cox (search), R-Calif., chairman of the House Select Committee on Homeland Security (search), told Fox News.

"There has been a distinct amount of communication intercepts to indicate there are good reasons to raise the alert," added former CIA operations officer Mike Baker.

Prelude to an Attack?

Some are wondering whether the surfacing of yet another Usama bin Laden audiotape may be a prelude to an attack somewhere in the world. When previous tapes have surfaced, some sort of large-scale attack has often followed.

As to the release of the bin Laden tape and whether it's directly tied to a future attack, Baker said: "I think the question regarding that is still up in the air but whether we should be on a heightened state of alert, I think that was the proper move."

Intelligence officials confirmed Monday that the voice on the latest tape was most likely bin Laden's.

"It is true that bin Laden tapes have, in the past, more often than not, coincided with some terrorist activity … but there may be just a coincidence more than anything in that," Cox said.

"I think because bin Laden himself remains the No. 1 focus in our efforts in Afghanistan and elsewhere — we want to capture him … when we hear from him, it's going to get a lot of attention."

Skip Brandon, former deputy assistant director of counterintelligence and counterterrorism at the FBI, earlier told Fox News that the correlation is not something to overlook.

"There's no question, should be no question in any of our minds, that the intelligence of law enforcement people around the world are very much aware of this," Brandon said.

Since the Sept. 11 attacks, the U.S. government has boosted its human intelligence network and tripled the number of Arabic-speaking analysts and operatives.

A U.S. intelligence official said those analysts corroborate information from various sources and compare it with past Al Qaeda tactics to determine whether a "disinformation" campaign might be under way to throw U.S. officials off of terror groups' true motives.

Although the government has not said exactly what these recent threats entail, they have passed on enough credible information that has led to the recent delay and cancellation of several international flights to and from Washington and Los Angeles.

On Monday, British Airways Flight 223's departure from London to Washington was delayed for the sixth day in a row while U.S. authorities double-checked certain information before the plane was cleared for takeoff.

Relatedly, the Maryland Transport Authority Police confirmed to Fox News that 100 percent of the vehicles entering Baltimore-Washington International Airport were being searched on Tuesday. Spokesman Greg Prioleau said the searches were an attempt to vary security tactics and that there was no specific threat that brought about the searches.

Airport officials told news outlets that the sweeps were not expected to create major delays entering the airport and still recommended that passengers arrive 90 minutes before their scheduled flights.

U.S. 'Closed to Terrorists'

Meanwhile, the Bush administration continues to share information with foreign governments to win the war on terror, and DHS is in its second day of performing advanced security measures on foreigners entering the United States through the nation's airports and seaports.

US-VISIT includes digitally scanning fingerprints and taking photographs of about 24 million foreigners entering the United States every year. The information is fed into a database that has a list of suspected terrorists or people affiliated with terrorist organizations.

All 115 U.S. airports that handle international flights and 14 major seaports will utilize the new system. The only exception to the rule will be visitors from mostly European nations, whose citizens are allowed to come to the United States for up to 90 days without visas.

Homeland Security Secretary Tom Ridge (search) said the program has already weeded out at least 20 people who are on record for being involved in criminal activity. A similar program is to be installed at 50 land border crossings by the end of next year.

The goal is to "make sure our borders are open to visitors but closed to terrorists," Ridge said in launching the program on Monday.

Although some Democrats want more money doled out to homeland security efforts when Congress returns from its recess Jan. 20, others said recent events have shown that money currently being spent on homeland security measures is being put to effective use.

Rep. Pete Sessions, R-Texas, told Fox News that $29 billion has been given to DHS this year. He said the security measures put into place within the last two weeks and the fact that U.S. agencies are getting more effective at gaining intelligence from overseas and using it to prevent future attacks, "is an indication about how well, not only Secretary Ridge and this president has done, but also what the Congress has done to be a part of this answer."

Fox News' Mike Emanuel, Pat Hendry, Liza Porteus, Kelly Wright and The Associated Press contributed to this report.