A "suspicious package" in New York's Penn Station triggered at least a partial evacuation today while bomb squad technicians investigated, city police officials said.
The scare was at least the third such incident of the day.
Within about a half-hour, people began returning to the station, according to a television crew from WABC-TV in New York, and police and emergency officials declared the incident over.
A preliminary report indicated a person may have tossed the suspicious package at an Amtrak clerk, shouted "bomb" and fled, according to other city emergency personnel. Police could not initially confirm that report.
Penn Station is the terminus for the Washington-to-New York corridor of Amtrak, the Long Island Railroad, New Jersey Transit, and numerous New York City subway lines. PATH subway trains between New York and New Jersey also are in the vicinity.
New York and New Jersey have been on heightened alert for danger to transit -- not only because of the London attacks but because of recent, unconfirmed information from a credible source that the Amtrak line between Washington and New York could be the target of an attack.
Terrorists' desire to target transit long has been known. But the recent information was specific enough for the FBI to send warnings to rail officials.
However, officials stressed the information, while specific, was unconfirmable, so the warnings were made as a precaution only.
In the wake of the most recent London attacks, public terrorism awareness has again been heightened. Officials in New York and other states with large mass-transit systems report an increase in reporting of suspicious packages and devices, ABC News has learned.
At the time of the Penn Station scare, the New York bomb squad had responded to at least two earlier reports earlier in the day, one reportedly near the bus terminal at 42nd Street and Eighth Avenue, possibly aboard a Greyhound bus, and another at 51st Street and Broadway.
Officials have sought the increased public awareness. And even when reports turn out false, they almost always have been from well-meaning citizens.