NEW YORK – The ghastly toll of the terrorist attack on the nation?s largest city came into focus Thursday, as more than 4,700 people were reported missing in the devastation of the World Trade Center. President Bush said he would visit New York and thank its people for exhibiting ?the bravery of America.?

The grim process of combing tons and tons of rubble went on.

Mayor Rudolph Giuliani said the city had some 30,000 body bags available to hold the pieces taken from the wreckage, and parts of 70 bodies had been recovered. There were just 94 confirmed dead; 30 or fewer had been identified. And 4,763 people had been reported missing.

?It could turn out we recover fewer than that; it could be more,? Giuliani said. ?We don?t know the answer.?

In a call to Giuliani and New York Gov. George Pataki, Bush said he would visit New York on Friday. ?I weep and mourn with America,? he said, describing Tuesday?s attacks as ?the first war of the 21st century.?

He said he looked forward to thanking the people who ?made a huge display, for the world to see, of the compassion of America and the bravery of America.?

The president will find a reeling metropolis. A vast section of the city has been sealed off, as emergency workers struggled to cope with the unprecedented destruction.

Work was slowed by hellish bursts of flame and the collapse of the last standing section of one of the towers taken out by suicide jets.

The rescue efforts were once again hindered by the battered infrastructure in lower Manhattan. The top 10 floors of the 53-story One Liberty Plaza, near the Trade Center site, began buckling and forced the evacuation of some rescue workers Thursday afternoon.

At one point authorities said five Fire Department rescue workers had been extricated from the rubble, two days after they were entombed in a sport utility vehicle. It turned out there were just two men, and they were trapped in an underground air pocket only briefly on Thursday.

A day before, five people had been pulled alive from the Trade Center rubble – three of them police officers.

The effort in New York was mirrored at the Pentagon, where 126 people were believed to be dead – among them a three-star Army general – and 70 bodies had been recovered.

The total deaths at the Trade Center and the Pentagon – as well as those on board the planes that crashed into them and into a grassy field southeast of Pittsburgh – would bring the total to more than 5,000.

That would be higher than the death toll from Pearl Harbor and the Titanic combined. A total of 2,390 Americans died at Pearl Harbor nearly 60 years ago, and the sinking of the Titanic claimed 1,500 lives.

A thick cloud of acrid, white smoke blew through the streets Wednesday after the four-story fragment of the south tower fell. Gusts of flame occasionally jumped up as debris was removed from the smoldering wreckage.

The vast search to uncover the terrorist plot stretched from Miami to Boston to Portland, Maine, and on to Canada and Germany. Up to 50 people were involved in the attack, the Justice Department said, with at least four hijackers trained at U.S. flight schools. Saudi fugitive Osama bin Laden remained a top suspect.

Attorney General John Ashcroft said authorities had ?thousands and thousands? of leads. He said they had determined that 18 hijackers were on the planes: five on each of two planes and four on each of the other two.

In Washington, Bush worked with Congress on legislation authorizing military retaliation, and officials disclosed that the White House, Air Force One and the president himself had been targeted Tuesday.

America?s NATO allies bolstered Bush?s case for military action, declaring the terrorist attacks an assault on the alliance itself.

Ripples continued to spread. The National Football League called off the 15 games scheduled for this weekend, and major-league baseball extended its hiatus through the weekend.

But gradually, some sectors returned to normal. The government gave the go-ahead for commercial flights to resume and some did, but schedules were expected to be in disarray, and heavy security was the rule.

Bond trading resumed Thursday, while Wall Street officials said the stock markets were expected to open again on Monday. The shutdown on the New York Stock Exchange was already longer than the two-day closure at the end of World War II; the next-longest lasted a week, after the 1929 crash.

In New York, the landscape was a haze of gray dust, splayed girders, paper and boulders of broken concrete. Firefighters armed with cameras and listening devices on long poles searched for survivors. German shepherds and golden retrievers clambered over the debris, sniffing.

A morgue set up in a Brooks Brothers clothing store received remains a limb at a time.

Three financial companies with offices in the complex had more than 1,300 workers unaccounted for. MMC, an insurance firm, said it had not been able to account for 600 of 1,700 employees; Keefe Bruyette & Woods, a securities firm, said 67 of 171 employees were missing. Cantor Fitzgerald, a bond firm, said 680 of its 1,000-person staff were missing.

Giuliani was among those who escaped Tuesday?s attack uninjured, bolting from a building barely a block from the site when the first of the towers collapsed.

More than 3,000 tons of rubble was taken by boat to a former Staten Island garbage dump, where the FBI and other investigators searched for evidence, hoping to find the planes? black boxes with clues to what happened in the final terrifying minutes before the crashes.

Insurance industry experts say the attack could become the nation?s most expensive manmade disaster ever, with payouts ranging from $5 billion to $25 billion.

The densely packed bottom tip of the island, an area roughly five square miles, remained off-limits to everyone but emergency workers. Volunteers emerged from the search-and-rescue mission with grisly tales as they cleared away the twisted steel and glass wreckage of the twin towers.

One body was carried out wrapped in an American flag. When workers hung another American flag from a piece of a transmission tower that apparently survived the collapse, ?everybody stopped and saluted,? said Parish Kelley, a firefighter from Ashburnham, Mass.

Kelley spent the day working in a crater left by the towers? collapse. As he picked through the rubble, he watched as a man?s body – a cell phone still clutched in his hand – was carried out.

At Bellevue Hospital, a firefighter almost had to have his leg amputated so he could be freed from the rubble, said Pataki, who visited the hospital to thank medical workers and speak with patients.

The governor asked him why he would risk his life. The unidentified firefighter told him: ?What do you expect? I?m a New Yorker.?