The Port Authority says that “out of an abundance of caution,” it will add more police at its facilities including the New York area’s airports, the George Washington bridge and the World Trade Center site.

The Port Authority made the announcement early Monday, hours after the U.S. said Osama bin Laden had been killed. It says the extra police is not a response to any current threat and that all its facilities will operate normally otherwise.

Also, New York Police Commissioner Ray Kelly has issued a message to all police commands reminding them that while there’s no information indicating a specific threat to the nation’s biggest city, officers should remain alert.

Eighty-four Port Authority employees died in the attack on the World Trade Center on Sept. 11, 2001.