WASHINGTON (Reuters) -
Technicians have confirmed that dozens of wireless signals have originated from the wreckage of the World Trade Center since Tuesday's attack as they deploy technologies in hopes of finding survivors, officials said on Saturday.
"We do have 50-plus open cases where we have had signals detected at ground zero since the attack," said Kark Rauscher, who is heading up a coalition of wireless companies helping look for survivors.
"We realize that we may be the only hope that some people have, so we're going to do everything we can," said Rauscher, Lucent Technologies Inc.'s director of system reliability.
In one case, two people apparently trapped together in the wreckage have placed separate calls, possibly with separate phones, although they have not been heard from for at least the past day, he said.
The ad-hoc "wireless emergency response team," composed of technicians from some of the major telecommunications companies, has begun searching for activity on about 2,000 wireless phone numbers of people believed trapped in the wreckage.
Although an active signal from a wireless device would not indicate that its owner has survived the attack, it could help rescue crews focus on air pockets and basement areas of the rubble where people may be huddled awaiting rescue, a Federal Emergency Management Administration spokesman said.
As wreckage is cleared away, the team hopes its "radio frequency sniffers" will be able to pick up signals blocked by the tons of concrete and steel.Wireless numbers for people missing after Tuesday's attack can be provided to BellSouth operators at