LONDON—Armed British police officers arrested a man carrying knives near Prime Minister Theresa May’s office in London on Thursday on suspicion of preparing an act of terrorism.
The 27-year-old man was detained by counter-terrorism officers on Parliament Street, a stone’s throw from the parliament building, May’s Downing Street office and government departments, during a stop-and-search in an ongoing security operation, police said.
A Western security source said the man, from London, was on the radar of counter-terrorism officers and the domestic intelligence agency MI5 before his arrest.
No one was injured in the incident, and May was not at Downing Street at the time because she was campaigning in northern England for a June 8 parliamentary election.
A source familiar with the investigation said the suspect had been arrested as part of an intelligence-led operation.
