British police have arrested a 27-year-old man near Britain's Houses of Parliament and other government buildings for the illegal possession of weapons and suspicion of preparing "acts of terrorism."
Police say the man was detained at gunpoint on Whitehall Street in London on April 27 after what they called a "stop and search as part of an ongoing operation."
Reporters saw at least two knives on the ground as police detained and handcuffed the suspect, who was dressed in black and carried a backpack.
The suspect had a long, untrimmed beard and a short, closely cropped haircut.
Police said no one was hurt during his arrest. Authorities did not immediately release the name of the suspect.
Numerous government ministries and other state institutions -- including Parliament -- are located on Whitehall Street, which also leads to Prime Minister Theresa May's official Downing Street residence.
Police immediately put the area on lockdown, blocking traffic on the busy street and nearby sidewalks.
Downing Street said the prime minister was not at her residence at the time of the incident.
Security has been increased near Britain's Parliament since an attacker on March 22 drove a vehicle into pedestrians on Westminster Bridge and then stabbed a police officer to death in front of Parliament.
Four pedestrians on the bridge were killed along with the attacker, who was shot dead by police inside the compound of Parliament.
Extremists from the so-called Islamic State (IS) extremist group claimed responsibility for the March 22 attack.
With reporting by AP and Reuters