Updated

Law enforcement is warning officials around the country that Islamic extremists may be using webcams as potential terror planning tools.

FOX News obtained a copy of a law enforcement bulletin issued Thursday by the Department of Homeland Security, FBI, and state and local law enforcement, entitled, "Webcams: a potential terrorist planning tool."

One Islamic extremist Web site recently had a posting titled, "You Can Spy on the Enemies," which provided a link to a live webcam at a U.S. international airport and promised more links in the future, the bulletin says. The airport webcam site allowed the viewer to control the camera, including zooming in on the terminal and cargo areas. Airport authorities disabled the webcam after they were notified of the posting.

The bulletin details how webcams could work against security efforts, particularly since they are popular, inexpensive tools that allow Internet viewers real-time visual feed from remote locations.

Many webcams operated by personal, commercial, or government entities transmit images of weather, geographic features, city skylines, famous squares, or traffic intersections and have little or no surveillance value, the bulletin says.

But webcams at U.S. critical infrastructure locations can allow would-be terrorists to scope out security measures, guard shift changes and pedestrian and vehicular traffic patterns.

"The Islamic extremist Web site posting and its reference to using webcams to 'spy' on airports demonstrate the continued intent of Islamic terrorists to conduct surveillance on the aviation industry and the possible use of webcams to surveil other critical infrastructure," the bulletin states.

FOX News' Catherine Herridge and Ian McCaleb contributed to this report.