WASHINGTON_U.S. mass transit systems should remain alert against possible terror attacks, the Homeland Security Department said in a new warning that highlighted suspicious activity at unnamed European subway stations last fall.
Homeland Security spokesman Russ Knocke said Wednesday there is no specific or credible intelligence to indicate U.S. transit systems are being targeted.
He described the notice, sent Tuesday, as a routine reminder for transit authority operators, state security advisers and police to remain on guard.
At issue were two incidents last November of what the notice described as a foreign man who was arrested in an unnamed European city after videotaping the interior and exterior of several subway cars and stations, including trash cans and stairwells.
The man taped nearly 17 minutes of subway pictures, the notice said, but "the camera contained no footage of tourist sites." Three other people were later arrested for similar activity, the notice said.
The incidents "prove indications of continued terrorist interest in mass transit systems as targets, and potentially useful insights of the terrorists' surveillance techniques," said the notice, a copy of which was read to The Associated Press.
<<Associated Press WorldStream -- 05/04/06>>