Scotland Yard: Cartridge Bomb Might Have Exploded Over Eastern U.S.

An explosive device found in a cargo plane in England last month probably would have exploded over the Eastern Seaboard of the United States if it had not been discovered, Scotland Yard said Wednesday.

The device was primed to explode about six hours after it was found, a senior U.S. counterterrorism source told CNN.

""Forensic examination has indicated that if the device had activated it would have been at 10:30 hrs BST on Friday, 29 October 2010,"" the Scotland Yard statement said. ""If the device had not been removed from the aircraft the activation could have occurred over the eastern seaboard of the U.S.""

Al Qaeda in the Arabian Peninsula, the Yemen-based arm of the al Qaeda terrorist network, claimed responsibility last week for the plot to send explosive devices on cargo planes bound for the United States.

White House spokesman Nick Shapiro said the findings by British authorities ""underscore the serious nature of the attempted AQAP attack and the challenge we all face in trying to prevent or disrupt such attacks.""

Shapiro cited ""the collective efforts of many dedicated intelligence and law enforcement professionals"" in the United Kingdom, the United Arab Emirates, Saudi Arabia and the United States for disrupting the attacks. "