A man arrested by armed police near an entrance to the Houses of Parliament remains in custody awaiting a mental health check, police said.
About a dozen officers swarmed around the suspect as he was held against a fence inside the Carriage Gates on Tuesday.
The man was Tasered after he ran toward officers and failed to stop, the Metropolitan Police said.
A man was arrested by Carriage Gates, inside the Palace of Westminster, on suspicion of trespassing on a protected site at around 11.55hrs on Tuesday, 11 December. A Taser was deployed. Enquiries into the circumstances continue. https://t.co/bzmTJwgLVU pic.twitter.com/NIujTT61eT— Metropolitan Police (@metpoliceuk) December 11, 2018
The entrance was the scene of a terrorist atrocity in March 2017 when Khalid Masood murdered unarmed police officer Keith Palmer.
At the time there was shock at the lack of an armed presence near the gate, and chief coroner Mark Lucraft QC found shortcomings in security at the site meant marksmen did not know where they were supposed to patrol.
Since the attack, security at the site has been beefed up, with a permanent armed presence at the entrance.
The man was taken away in a police car shortly after 12.15pm.
The incident is not believed to be terror-related.
Project Servator uniformed officers working with plain clothes officers providing the public with reassurance after earlier events at Parliament Square. #ProjectServator #actionscounterterroism @CityWestminster @wabbey pic.twitter.com/k75Xibl8gh— MPS Westminster (@MPSWestminster) December 11, 2018
A Metropolitan Police spokesman: “At around 11.55am, a man tried to gain entry to the grounds of the Palace of Westminster via Carriage Gates, and ran towards officers posted there.
“He did not comply with officers’ requests to stop. A Taser was deployed.
“The man was subsequently arrested on suspicion of trespassing at a protected site, and taken to a police station where he remains.
“The arrested man will have a mental health assessment.”