An armed police officer stands outside the Houses of Parliament, central London November 26 , 2014.
Paul Hackett—REUTERS
January 8, 2015 10:00 PM EST

Fears are growing the U.K. may be the next European target of a terrorist attack, following the mass killing at the Paris offices of satirical magazine Charlie Hebdo.

Andrew Parker, head of British intelligence agency MI5, said on Friday that an attempted “mass-casualty attack” by al-Qaeda was a growing possibility, the Telegraph reports.

Parker’s statements come two days after 12 people were killed by three gunmen at the Charlie Hebdo office in Paris. The British security chief said his agency has stepped up surveillance of fanatics who could try and imitate Wednesday’s attack.

“Although we and our partners try our utmost, we know we cannot hope to stop everything,” he said.

Parker added that although three terrorist plots had been thwarted in the past few months, the difficulty of monitoring online communications made it inevitable that one of them would soon succeed.


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