Cuba, seeking to reassure its people after Fidel Castro temporarily stepped down from power for surgery, released a statement from the long-time leader saying his health was stable and the defence of the island guaranteed, even as it sent more police today into neighbourhoods that have seen civil disturbances in the past.

TERROR strikes from the sea could be even more catastrophic than those from the air, intelligence officials say. They fear a hijacked oil tanker could be rigged with explosives or a radioactive dirty bomb could be smuggled ashore in a shipping container.