New alert over reprisal attacks

A "continued flow of daily intelligence" pointing to new attacks on America is behind today's decision by the US government to extend a national terror alert into the spring.

Americans are being told to be on their guard at least until March, and report any suspicious activity to the authorities. This is, in part, because the CIA and the Pentagon strongly believe that Osama bin Laden supporters are determined to inflict reprisals for the bombing in Afghanistan and the deaths of senior figures in the al Qaeda and Taliban leadership.

Adding to the US government's anxiety is the possibility that Bin Laden himself may have been killed by massive air strikes yesterday on a site in Afghanistan near the Pakistan border where unusually intense security suggested he was present.