WASHINGTON - The number of people who are missing and presumed dead at the site of the World Trade Center in New York rose sharply yesterday, to 6,333. For several days, the number had been reported to be 5,422.

Mayor Rudolph W. Giuliani said the toll was raised to reflect the number of foreigners believed to have been killed in the terrorist attack last week.

People from more than 60 nations are thought to be among the victims. Britain alone has said it lost 250 citizens.

After more than a week of holding out hope of finding people alive in the ruins, Giuliani now says it is all but certain that no one will be found alive. A total of 241 people have been confirmed dead.

As Giuliani led 40 U.S. senators, including Sen. Barbara A. Mikulski of Maryland, in a tour of the rubble, the first of about 35,000 National Guard and Reserve forces were called to active duty.

The call-up is part of a "homeland defense" drive as the Bush administration plans military retaliation for the terrorist assaults.

The Pentagon said 5,131 members of the Air National Guard and Air Force Reserve from 29 units in 24 states and the District of Columbia had been called up.

The order includes 100 members of the 113th Fighter Wing at Andrews Air Force Base in Maryland, along with four of their F-16 Fighting Falcon warplanes.

The Air Force citizen soldiers are pilots and ground crews who will fly random combat patrols at 26 bases around the country.

Army special operations forces are part of the deployment, along with Air Force commandos who fly aircraft and helicopters and take part in search-and-rescue operations, officials said.

Special operations forces, the elite units of the services, include the Army Green Berets, Rangers, Delta Force and Navy SEALs.

Fort Bragg is the base of the 3rd and 7th Special Forces Groups. The Army base is also home to the most secretive element of the Special Forces: Delta Force, the commandos who specialize in counter-terrorism and assaults.

Officials say that Air Force special operations forces are also part of the deployment. Those commandos fly MC-130 cargo planes that can move troops and supplies into hostile areas.

The deployments involve about 100 aircraft, including B-1B and B-52 bombers, along with surveillance, cargo and refueling planes.

'Sustained land operations'

Army Secretary Thomas E. White said yesterday, "We have a very strong Special Operations capability in the Army, and I'm sure it will be used." He declined to discuss which units would be called.

The Army, he said, is "ready to conduct sustained land combat operations."

Defense Secretary Donald H. Rumsfeld said the military campaign against terrorism would require Pentagon planners "to fashion a new vocabulary."

"What we're engaged in is something that is very, very different from World War II, Korea, Vietnam, the [Persian] Gulf war, Kosovo, Bosnia," Rumsfeld said. "It is very different than embarking on a campaign against a specific country within a specific time frame for a specific purpose."