WOODBURY - Security all across the region remains heightened even after the Sept. 11 memorial service at Ground Zero.

Officials had warned earlier this week of a possible al-Qaida threat involving car bombs targeting sites in Washington, D.C. and New York City.

Heavily armed police patrolled the area surrounding Ground Zero and established checkpoints at train stations, bridges and tunnels as well as random checkpoints in other locations.

At least eight different law enforcement agencies were patrolling Penn Station in Manhattan, according to authorities.

Officials say that while the visible presence has been beefed up, they also increased patrols by undercover police.

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