BRITAIN faces a growing threat from terrorists at home and abroad and “cannot hope to stop” every plot, the boss of MI5 has warned.
Andrew Parker said Al Qaeda terrorists in Syria were trying to direct atrocities here and planning “mass casualty attacks” against the West.
His chilling warning came as French police continued the hunt for brothers Cherif and Said Kouachi, chief suspects in the Paris magazine massacre in which 12 people were shot dead.
Mr Parker, 52, warned that the terrorist threat was growing at the same time as MI5’s ability to track terrorists was being reduced.
Extremists are finding more secretive ways of communicating online and avoiding being tracked by the security services.
Mr Parker said: “If we are to have the best chance of preventing such harm, we need the capability to shine a light into the activities of the worst individuals who pose the gravest threats.