NEW YORK — Crews working in the smoldering ruins of the World Trade Center have begun assembling giant cranes capable of lifting hundreds of tons of debris at a time.
The delicate search continues for victims of the Sept. 11 terrorist attacks. But with the powerful cranes — one 420-feet high and with a base the size of a basketball court — workers will be able to remove more debris and larger chunks blocking access to parts of the wreckage.
"Every day we come down here, another 50 feet off the pile is gone," said Brian Bowman, 26, a Verizon worker restoring phone service near the site. "Every day we come down here, there's a new crane."
The official number of people missing in the rubble dropped to 5,960 on Thursday. Mayor Rudolph Giuliani said the number was lowered after a recheck of victims lists, compiled primarily from missing persons reports and information from foreign consulates.
As debris is cleared from the 16-acre site, human remains continue to be removed for identification. Forensic scientists say the majority of remains collected will be identified, mostly through DNA comparisons. So far, 305 deaths have been confirmed.
Dr. Robert Shaler, chief of forensic biology in the New York City medical examiner's office, said most victims examined died from "blunt trauma" and others from burns, smoke inhalation and injuries from sharp debris. Some likely were crushed by falling debris, he said.
"If you stare at the debris and think of all the people buried there it will get to you," said Peter Russo, 55, a carpenter from Old Bridge, N.J., who was building sheds for crews working at the site. "I have to look at it as a job, that the cleanup and rebuilding needs to be done."
Tons of steel and concrete cover the blocks where the 110-story World Trade Center towers stood.
On the 10th-floor roof of a nearby building, a color guard ceremony was held Thursday to honor the veterans who died in the collapse.
Broken glass littered the rooftop where the color guard of active Marines in uniform and former or reserve Marines from the police department, all in hard hats, flew the flags of the United States and its Marine Corps, Navy, Air Force, Army and Coast Guard.
As the ceremony ended, the color guard and some workers below snapped salutes.
On the building, a banner read: "We Will Never Forget."
"We don't know how many veterans were killed in this terrorist act," Marine Maj. David Andersen said. "We may never know. But we do know there were many among the rescuers and the other victims and this is to honor them all."
Away from the site, mandatory carpooling rules intended to ease traffic jams that have slowed the city since the attacks were in place for a second day Friday.
Motorists in New Jersey waited for an hour going into New York through the Lincoln Tunnel and some single-occupant cars were turned away. The traffic jam looked familiar to Weehawken Police Sgt. Mitchell Chasmar.
"Inbound is stopped, and westbound is crawling. I advise walking," Chasmar said. "It doesn't look any worse to me than a normal rush-hour."
He estimated that New York-bound traffic was backed up about two miles, to the New Jersey Turnpike, which also would occur before the attacks.
Vehicles crossing bridges and tunnels into southern Manhattan between 6 a.m. and noon Friday were again required to carry at least two people.
"I don't think it's going to get any worse because everyone knows what the deal is," said Abraham Ninan, a traffic agent at the Queensboro Bridge.
City Transportation Department spokesman Paul Kurtz said about 4 percent of cars carrying only the driver were turned away Thursday.
Giuliani said the restrictions would be evaluated after Friday and there was a possibility they might be extended.
On Saturday, the Empire State Building's observation deck was to reopen. Except for a brief trial period Sept. 15, the 86th floor observatory had been closed to the public since the terrorist attacks.
With the collapse of the twin towers, the building again became the city's tallest skyscraper.