With the tenth anniversary of the Sept. 11 terror attacks looming, security agencies are scrubbing communications for any sign of a terror plot and undertaking massive security operations in the Northeast.
So far, officials told ABC News they have no specific intelligence of any anniversary plot. There is zero intelligence of such a plot, and none of the "chatter" that has often been prior to major attacks, according to a person briefed on U.S. Intelligence.
But based on the exhortations by Osama bin Laden that Al Qaeda and its associates across the globe strike America on the anniversary, the security cordon around the anniversary event in New York and no less than three expected presidential visits is extremely tight.
The NYPD has teams of specially trained divers on alert, a massive presence in the subway system is planned, and a blueprint to pre-deploy specially equipped convoys across the city -- well outside the security cordon around lower Manhattan -- has been outlined.
Those convoys, replete with bomb technicians, hostage negotiators, snipers and heavy weapons teams -- as well has highway units ready to whisk key personnel at high speed to any threat location -- will be on the ready across the five boroughs.
According to sources involved in weeks of high level meetings involving New York, police, regional law enforcement and transit police executives, FBI supervisors and representatives of the Secret Service and intelligence agencies, the pace is now non-stop.
But it isn't just Sept. 11 anniversary that is consuming the hundreds of man hours in planning.
Beginning Sept. 8 with the docking of the USS York in Manhattan, there begin several weeks of back-to-back and overlapping high profile events -- all considered by security officials to be ripe terror targets.
The New York Mets are playing a string of home games through the week of Sept. 11 and the Men's Final of the U.S. Open occurs on the afternoon of Sept. 11. New York's famed fashion week is set to begin Sept. 8 at the same time a world surfing championship continues on the nearby beaches. The U.N. General Assembly opens a week after Sept. 11.
President Obama will make three trips to the tri-state area -- first to Patterson, N.J. on Sunday before participating in the Ground Zero ceremony on Sept. 11. He'll be back in New York on Sept. 19 for the U.N. General Assembly opening.
The FBI crisis team is working full throttle to assist the NYPD, a senior FBI official told ABC News, and hundreds of agents including hostage rescue and hazardous material experts will be on duty. The Joint NYPD-FBI Terrorist Task Force is on high alert.
There are so many targets to protect, senior police officials say, that they are ordering additional concrete barriers as they do not have enough tons of the barriers in stock for all the areas that need protecting.
Outside of New York FBI agents at each of the bureau's 56 field offices across the country are reviewing all active cases, and to reaching out to informants for new terrorism leads as well as re-examining old material "to make sure we haven't missed something," one official said.
Another measure the FBI has in place is the Operation Tripwire program. The program examines unusual purchases or other suspicious behavior for possible clues to an impending attack.
For example, in the past, the Bureau has queried businesses as to whether scuba gear was bought in large quantities or if there has been large purchases of certain chemicals at beauty salons.
Another federal agency involved in security planning, Alcohol, Tobacco, Firearms and Explosives , recently sent a letter to businesses involved in the selling of explosives, encouraging them to "exercise increased awareness and vigilance as the anniversary approaches."
"The security of your explosives storage sites is very important, and you should heighten your security precautions in light of the anniversary," the letter said.
Transportation Security Administration Director John Pistole said in an interview this week that the TSA is "doing a number of enhanced detection and prevention activities" as the Sept. 11 anniversary approaches.
Amtrak has begun to conduct more passenger and baggage screenings, is increasing the use of K-9 explosive detection teams, and expanding police patrols at stations, on trains, along the tracks and other key rail infrastructure, officials said.