A man has been arrested outside Houses of Parliament by armed police, with witnesses saying he was shot by a Taser gun.
Police were called to a disturbance on Friday (June 16) morning, and arrested a man, in his 30s, on suspicion of possession of a knife.
Police say they "remain open minded as to whether terrorism was a motive".
Scotland Yard said the incident happened shortly after 11am.
A statement read: “At 11.10am on Friday June 16 a man was detained near to the Palace of Westminster.
“The man - aged in his 30s - was arrested on suspicion of possession of a knife.
“There are no reports of any injuries.”
Police reacted after shouts of “knife knife knife” were heard.
Armed police ran towards Carriage Gates in response to shouting from outside.
It’s understood a man was held on the ground outside the gates, with police seen picking items up off the floor.
The bearded suspect, wearing black trousers and a grey sweatshirt, was led away into a van by officers after being detained for around 30 minutes.
No injuries have been reported.
He was held with his arms against his back just yards from the forecourt of the building, where PC Keith Palmer was stabbed to death by terrorist Khalid Masood in March.
Security around Westminster was tightened following the attack by Masood, who was shot dead after fatally stabbing PC Palmer as he guarded Carriage Gate.
The Mirror’s deputy political editor Ben Glaze was at the scene. He said in a tweet at the time: “Armed police currently dealing with an incident outside Parliament.”
He added: “Carriage Gates at Parliament have been closed. We heard shouting and saw a policeman with his gun raised outside. Haven’t heard any shots,” before posting a photo of the scene outside Parliament.”
Eyewitnesses told how the man was wrestled to the floor as armed police raced to the scene.
Aaron Simons, who was walking from Westminster Tube station to College Green at the time of the incident, told Mirror Online: “I had my headphones in and wasn’t really concentrating but then heard shouting from the police and people starting running the other way.
“I looked up at a man was being wrestled to the ground by a couple of policeman.
“He was struggling on the ground and a load of armed police ran out and trained their guns on him.
“They also then shut the gate immediately and one of the officers tasered him.”
A review of security at the perimeter of the parliamentary estate was ordered by Commons Speaker John Bercow following the terror attack in March.
The use of armed officers and physical barriers has become more visible, while a permanent barrier has been erected to protect pedestrians on Westminster Bridge, where Masood murdered four people and injured more than 50 others by mounting the pavement in a car.
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