Thousands of Americans unaccounted for
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(CNN) -- The U.S. State Department is working to find thousands of Americans unaccounted for days after powerful tsunamis struck countries bordering the Indian Ocean.
No exact numbers are available, State Department spokesman Richard Boucher said, but "we're working at any given moment 2,000 to 3,000 names now that we're looking for."
"We shouldn't assume the worst. ... There are often Americans who are outside of the regions that directly suffered who might not have gotten in touch."
Authorities have reported more than 116,000 deaths in at least 11 countries after Sunday's tsunamis that were triggered by a magnitude 9.0 earthquake. (Full story)
Boucher said the department was getting about 400 calls per hour from concerned relatives seeking their loved ones.
"In many cases, we are getting lists of these people out to embassies," Boucher said. "Embassies then are able to track them down or hear from them or identify them."
Names are constantly being added to the list as new calls come in from families, he said.
Boucher said 12 Americans are known to have been killed -- seven in Sri Lanka and five.
People are being asked to visit hospitals and morgues to identify Americans, Boucher said.
More Americans are in Thailand than in any other affected nation, but they are being sought in other countries as well, he said.
The Thai government has assured U.S. officials, amid concern about mass graves, that the remains of non-Thai citizens will not be buried without proper identification, he said.
Photographs, fingerprints and DNA samples are being taken and the location of foreigners' remains is being monitored by the government, Boucher said.
"Our consular affairs task force has been up and running 24 hours a day," he said.
"They're responding to calls, they're responding to faxes. ... The task force itself is placing calls to families to get more information or, in many cases, to pass on information that we can find."
The toll-free number to the task force is 888 407-4747.
Boucher offered advice for Americans who may be traveling in southern Asia, even if they are far away from sites where the tsunamis struck:
"Call your mother. This is a time where people who know they're hundreds of miles away from ... where the disaster might have occurred need to call home and tell their relatives, who know it's only a quarter-inch on the map."