• Metropolitan Police confirm taser was used in central London at 11:50am
  • Photos show man holding knife to his throat during Changing of the Guard
  • Queen and Prince Philip were at Sandringham Estate in Norfolk at the time
  • Man arrested on suspicion of affray and has been taken to a police station
Holding a blade to his own throat, this was the moment a knifeman brought chaos to the Changing of the Guard ceremony at Buckingham Palace yesterday.

The middle-aged man walked through crowds of tourists clutching two large kitchen knives before police surrounded him and used a Taser stun gun to disarm him.

As a policeman shouted a warning call of 'Taser, Taser, Taser' to his colleagues, the knifeman lunged forward, brandishing a six-inch blade in a series of swipes, before falling to the floor as he was stunned by the electrical charge.

Dramatic: Police officers tasered a man holding a knife to his throat outside Buckingham Palace yesterday
© Youtube/Grant Shepherd
Scary: The dramatic incident saw the man brandish two knives in front of hundreds of terrified tourists
© Youtube/Grant Shepherd
Down: The man charged towards a police officer outside Buckingham Palace who fired a taser gun at him
A video showed the man, in his 50s, shouting and holding the knife to his throat as he walked past the Victoria Memorial, towards the gates of the palace.

Police officers shouted to tourists to keep away from the man as they raced to surround him.

The man, who clutched a set of wooden beads and wore a flat woollen hat similar to the pakuls traditionally worn by men in parts of Pakistan and Afghanistan, was later arrested.

The drama unfolded as crowds gathered outside the palace before the midday Changing of the Guard ceremony, one of London's most popular tourist attractions.

Witnesses described seeing the bespectacled man breaking through a barrier and walking towards the palace before he was stopped and surrounded by police.

Eyewitness Kevin Burrows, 33, said: 'He had a knife in each hand.

'The police were on him in seconds, he didn't have a chance of getting close to anyone.
© Twitter/Josh Greenberg
The moment: This photo (unpixelated at source) was posted on Twitter by Josh Greenberg, captioned: 'Another photo from #Buckingham palace moments ago - Male with a #knife to his neck #Tasered by #Police'
'They surrounded him, they were telling him to calm down, and then a policeman Tasered him.' Mr Burrows, a kitchen porter from Surbiton, Surrey, added: 'The police were fantastic, it was all over in minutes. The procession was diverted away from him and the band just kept playing.'

Another witness, Grant Shepherd, filmed the incident and put it on YouTube. He described the scene in a Twitter message, saying: 'Crazy man with a knife to his throat just stopped the changing of the guard at Buckingham Palace.'
© PA
Left behind: Knives, a hat and taser wire in an cordoned off area outside Buckingham Palace in central London
© PA
Police standing guard: A cordoned off area containing knives, a hat and taser wire outside Buckingham Palace
The Queen and the Duke of Edinburgh were at Sandringham but were understood to have been informed about the drama. Scotland Yard is responsible for security at the palace and armed officers maintain a round-the-clock presence there, even when members of the Royal Family are not in residence.

Police cordoned off the area where the Taser was fired, some 30 yards from the palace gates.

The man, who has not been named, was checked by medics and arrested on suspicion of affray. Shocked tourists said police told them the man could have 'mental health issues'.

In June 1982 an intruder armed with a knife managed to get on to the palace forecourt before he was stopped.

A month later Michael Fagan got inside the Queen's private chambers while the monarch was still in bed.