US port closed

A major US port in the state of North Carolina has been closed after containers carrying explosive material were found punctured in Morehead City.



The chemical involved, known as PETN, is a powerful explosive.



PETN, or pentaerythritol tetranitrate, is used both in military ammunition and for industrial explosions.



It was also the substance allegedly used by a Nigerian man accused of trying to destroy an airliner about to land in Detroit on Christmas Day.



According to a US police spokesman, while no injuries have been reported, people have been told to leave the area.