A man holding a knife to his neck has been tasered outside Buckingham Palace during the Changing of the Guard ceremony. Scotland Yard said the incident happened yesterday. The man was arrested. Grant Shepherd, an onlooker at the scene tweeted: “Crazy man with a knife to his throat just stopped the changing of the guard at Buckingham Palace.”

Stunned: Cops tasered the unidentified man who is believed to be in his 50s after he held a knife to his throat in front of Buckingham Palace. Pics/twitter