The source said that Adlene Hicheur had been ‘pinpointing nuclear targets’ but would not be more specific…

Last night, MI5 was understood to be examining their British links amid fears that they were plotting to launch a nuclear attack in the UK. A spokesman for the Rutherford Appleton Laboratory refused to release details about Adlene Hicheur’s time there.

Fears were growing that the men may have been in a position to smuggle nuclear material out of a secure lab for use in a ‘dirty bomb’ attack, or to plant explosives inside the sensitive facility.

According to European intelligence sources, MI5 had been warned that the suspects ‘are outstanding scientists who had been honing their techniques in nuclear fusion across the world.