Dramatic video shows the aftermath of a security alert in Whitehall where a man has been arrested under terrorism laws.
Armed police put Westminster on lock-down as images from near the Treasury building showed police forensic officers photographing what appeared to be several knives on the ground.
Footage also shows pedestrians being moved away from the area by armed officers as investigators swarm the area and examine the blades.
Police said no one was injured in the incident, which took place just yards away from Parliament where terror attacker Khalid Masood killed himself and five others in March.
The suspect was detained at the scene for several minutes within view of journalists and passers by before he was eventually taken away by police.
A police spokesperson said "knives have been recovered" from the man, who was arrested "following a stop and search as part of an ongoing operation".
Detectives from the counter-terrorism command are investigating, and said that as a result of this arrest there is no immediate known threat.