GETTY Armed police were attacked by a US tourist outside Buckingham Palace

FREE now SUBSCRIBE Invalid email Make the most of your money by signing up to our newsletter fornow We will use your email address only for sending you newsletters. Please see our Privacy Notice for details of your data protection rights.

Ryan Robinson, 36, of Hawaii, punched PC Ben Collins at least four times to the face and tried to grab his Taser on Wednesday evening. When PC Simon Leckie tried to intervene, shouting "Armed police. Stand still" and pointing his weapon at the American, Robinson knocked him to the ground. He then pulled the two officers to their feet in "an extraordinary display of strength", prosecutor Henry Fitch said, before punching PC Collins again. Robinson was heavily intoxicated and it took several other officers before he could be restrained and arrested, the court heard. The two victims had been on patrol awaiting the arrival of the Prince of Wales and had asked Robinson to get out of the way behind the barriers when he attacked them.

He appears to have taken exception to the way in which PC Collins dealt with him, believing he was behaving rather officiously Michael Boyd

Robinson appeared at Westminster Magistrates Court on Friday in a dirty shirt with a bruise to his eye and pleaded guilty to two counts of assaulting a police officer. The court heard PC Collins suffered bruising to his face and ribs, while PC Leckie suffered a tendon injury in his wrist and was still unable to move it. Michael Boyd, for Robinson, said he had been staying at the Smart View Hostel in Hyde Park and had been travelling in the UK for about a month before the attack. Mr Boyd said: "He appears to have taken exception to the way in which PC Collins dealt with him, believing he was behaving rather officiously."

PA The officers were awaiting the arrival of Prince Charles