By Michael Weissenstein
The Associated Press

NEW YORK - Trash cans are welded shut, armed guards are watching rail yards and thousands of cops are patrolling Penn Station. North America's busiest train station is the epicenter of the city's largest police deployment in memory.

Officers will be aboard every one of the more than 1,000 subway and commuter trains that roll daily into the labyrinth of platforms and tunnels beneath Madison Square Garden. Passengers will share platforms with bomb-sniffing dogs and chemical weapons detectors.

ELECTION 2004

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Security officials say police, National Guard members and state troopers will blanket the convention and the nation's largest public transit system, keeping them safe and running smoothly.

But vulnerabilities remain in a system that carries more than a half million passengers a day. Authorities are taking no chances, announcing Saturday they arrested two men on charges of plotting to bomb a midtown Manhattan subway station and other targets, though there was no clear connection to the convention.

High among the safety concerns are the underwater tunnels - some miles long and a century old - that connect Penn Station by train to New Jersey and Long Island. Many of their ventilation systems, firefighting water lines and passenger escape routes are decrepit.

Amtrak, New Jersey Transit and the Long Island Rail Road began installing $1 billion worth of new vents, water pipes and walkways in the early 1990s. So far, only $123 million has been spent, and the tunnel project is four years from completion. "Many of them go for a mile and a half with no escape route, no ventilation," said Sen. Charles Schumer, D-N.Y. "God forbid a bomb should go off."

Amtrak spokesman Cliff Black said Amtrak has been struggling to improve safety with a limited budget. "Amtrak has been constrained by capital funding since its inception and we are in the process of playing catch-up," he said.

After the Sept. 11, 2001, attacks, the Metropolitan Transportation Authority received $591 million in federal funds to strengthen weak points of bridges and tunnels, and to install digital cameras, sound-activated alarms and other devices at sensitive locations. It has spent about $100 million, but construction has not begun.

MTA security chief William Morange said the agency was moving quickly to improve security without rushing poorly designed measures into action.

"If it isn't done right you might as well not even do it at all," he said.

Penn Station will be patrolled by 3,000 police officers. As many as 7,000 more officers will protect Madison Square Garden, the subways and convention-related sites - joined by the Secret Service, FBI and thousands of corrections officers, transit police and state troopers from New York, New Jersey and Connecticut.

"Everything that can be done has been done to address security in and around the Garden and Penn Station," said A.T. Smith, Secret Service special agent in charge of the New York field office.

New Jersey Transit, which moves 60,000 passengers into Penn Station on a typical workday, is implementing some of the tightest security measures. On-board trash receptacles are being welded shut, all but one restroom on each train will be locked, use of overhead luggage racks will be prohibited and teams of officers will search every car at its last stop before Penn Station, said George Warrington, the agency's executive director.

Amid concern about vehicle bombs, uniformed and plainclothes officers will be riding city buses, particularly those passing through open streets near the convention.