Hundreds, perhaps thousands, of foreigners worked in the towers.
On Thursday, people around the globe awaited word of whether their sons, daughters and colleagues had survived.
Dramatic stories began to emerge - an Irishman said his brother who worked in the towers survived, but his sister on a hijacked plane did not. From China, a woman escaped and saw her office building melt like "chocolate."
Nearly everywhere, people simply hoped for the barest of details.
As is the case with the overall count, the number of foreigners among the missing remained unclear. But as governments try to track down their citizens, it appeared the number of dead could easily rise into the hundreds.
According to Japan's Foreign Ministry, roughly 100 Japanese nationals, including dozens of tourists, were unaccounted for.
There were 31 Japanese companies with branch offices in the Trade Center towers, and at least 22 workers were among the missing.
"We are working around the clock," Yoshinori Ide, a spokesman for Japan's Fuji Bank, said from an emergency center to coordinate the bank's search for 12 missing employees.
Bank employees who survived the attack were calling and visiting hospitals in search of missing colleagues, who mostly worked on the 79th through 81st floors of the second tower.
At least 50 Bangladeshis have been confirmed dead in the World Trade Center attacks and many more reported missing, government spokesman Safi Sami said. Many worked at restaurants in the towers, he said.
Britain's casualties appeared to be even heavier.
"I understand that the number of confirmed British deaths is now approaching 100," Foreign Secretary Jack Straw said Thursday.
"Although these ... cannot be anything but imprecise estimates, the total number of British deaths is unlikely to be less than the middle hundreds and maybe higher."
That would be well above past Irish Republican Army attacks and the 1988 bombing of a Pan Am jetliner over Lockerbie, Scotland, that killed 33 Britons.
In Ireland, television viewers heard John Clifford tell of how his brother escaped unscathed from the World Trade Center, only to learn later that his sister and a young niece were in one of the planes that hit the towers.
Clifford, of Cork, told Irish television that his brother Ronnie, 47, survived but his sister Ruth, 45, and her 4-year-old daughter Juliana had died.
"Tragically, my sister hit the tower building as my brother was on the ground floor. He's safe now. He's very traumatized."
Another survivor was Sun Lingling, 46, who handles the China Daily newspaper's distribution in North America.
According to an interview with her in the paper, she stumbled down 33 flights of stairs, losing only a shoe. She then watched from outside as the tower where she had worked for eight years collapsed.
"It was as if a huge piec of chocolate had been melted down," Sun said.
Most of the 27 South Koreans listed as missing were employees of firms in the World Trade Center.
The only Korean confirmed dead, however, was aboard the hijacked United Airlines plane from Boston. Kim Ji-soo, 37, was flying with her American husband and 2-year-old daughter to visit her grandmother in Los Angeles.
"I was so looking forward to seeing her," the grandmother, Kim Ok-hee, told The Associated Press. "My granddaughter is extra special to me because I had brought her up until she was 6. Both of her parents died from cancer."
Nine Australians were confirmed dead and another 85 were missing. Defense Minister Peter Reith said he expected the toll to rise.
"We have little doubt that we will need to brace ourselves for more," he said.
In the Philippines, journalist Cookie Micaller said her sister, Cynthia Wilson, a naturalized U.S. citizen, was on the 79th floor of one of the towers and used a cellphone to call an uncle in New York five minutes before the building collapsed.
"She said, Please pray for me. We need your prayer.' The conversation was cut off, and she never called again," Micaller said.
The Mexican government news agency Notimex reported there were 100 to 150 Mexicans working in the World Trade Center and at least 12, some who had worked at the restaurant Windows on the World, remain unaccounted for.
Mexico's consul in New York, Salvador Beltran, said it would take weeks to know how many had died.
A Chinese couple from Beijing who had been visiting their daughter in Virginia were killed on the plane that struck the Pentagon, an official at China's embassy in Washington said.
China's Foreign Ministry said two other Chinese were killed, but it did not know where.
Eleven of the 18 Chinese organizations with offices in the World Trade Center had accounted for their employees. Five people remained missing, spokesman Zhu Bangzao said. Worried families posted messages on the Internet.
"Cai Wenke in New York, your relative Cai Guangchang in China is very concerned," read one message on the Web site of Phoenix TV, a Hong Kong-based satellite broadcaster. "If you are safe, please contact Cai Guangchang immediately."
Three Lebanese were reported missing, including two who worked at the World Trade Center and one aboard the first plane that hit it. Officials in Sweden said a 25-year-old man who worked in the World Trade Center was unaccounted for.
By Chisaki Watanabe
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