N.Y. Subway Threat

A portion of the Amtrak waiting area closed for about two hours at Penn Station while New York City and Amtrak police officers in special bio-chemical suits investigate a suspicious package on Friday, Oct. 7, 2005. Security has been increased throughout the city's transportation systems following the announcement of a terrorist threat reportedly aimed at the subway.

A portion of the Amtrak waiting area in Penn Station was closed by New York City and Amtrak police to investigate a suspicious package found on Friday, Oct. 7, 2005. New York Police Commissioner Ray Kelly says a green liquid that leaked from a soda container turned out to a drain-cleaner substance. He describes the incident as a "prank."

Manhattan's downtown skyline is muted in fog as a subway train leaves a Brooklyn station in New York, Friday, Oct. 7, 2005. As the Department of Homeland Security expressed doubts, New York City officials on Thursday announced a creditable terror threat for the city's transit system.

New York City Mayor Michael Bloomberg, second from right, rides the subway downtown to New York City Hall, Friday, Oct. 7, 2005, in New York City. Bloomberg vowed to ride the subway to work during an Oct. 6 press conference about a credible security risk in the city's train system.

Commuters pass through the Grand Central subway station, Oct. 7, 2005, in New York City. The city has mobilized hundreds of officers to subway stations in response to a "credible threat" to the subway system. Most New Yorkers seemed unfazed by the threat.

Police monitor the Stamford, Conn., train tracks that service Amtrak and Metro-North, Friday Oct. 7, 2005. Connecticut Gov. M. Jodi Rell on Thursday night ordered increased security on Metro-North trains because of what New York City officials called a credible threat of a potential terrorist attack to the city's subway system.

New York City police officers check subway cars at Columbus Circle on Friday, Oct. 7, 2005. Security in the city's mass transit system has been increased following Thursday's announcement of a specific terrorist threat to the subway system.

A New York City police officer looks into a woman's bag during the search at the Columbus Circle stop Friday, Oct. 7, 2005. Security in the city's mass transit system has been increased following Thursday's announcement of a specific terrorist threat to the subway system.

A sign asking subway passengers to report suspicious activities is posted on a platform as passengers are seen boarding a train, Thursday, Oct. 6, 2005, in New York. City officials stepped up mass transit security Thursday, saying they had received a credible threat that New York's subway system could be the target of a terrorist attack in coming days.

New York City Mayor Michael Bloomberg makes remarks concerning the heightened state of alert in the New York City subway system at a press conference Thursday Oct. 6, 2005, in New York. He is joined by Mark Mershon, assistant director in charge of the FBI's New York field office, left, and New York City Police Commissioner Raymond Kelly.

Security Task Force guards watch for any suspicious activity as morning commuters pass through New York's Grand Central Terminal, Friday, Oct. 7, 2005. Straphangers heeded the mayor's business-as-usual advice Friday after a newly disclosed terrorism threat against the New York subway raised the specter of an attack with explosives concealed in a baby stroller.