The man was detained after he was seen with a knife near the security fence surrounding the palace, a Scotland Yard spokesperson said.
"At 10:40 a.m. patrolling officers detained & arrested a man in The Mall in possession of a knife. No injuries. Not believed to be terrorist related," a tweet on the Metropolitan Police page said.
Nobody was injured in the incident outside the Palace and the knife was recovered, the Guardian reported.
The traditional Changing of the Guard ceremony at the Palace was cancelled on Wednesday, while the Houses of Parliament were closed to the public following an attack late Monday outside a pop concert venue in Manchester that left 22 dead and 64 injured.
Scotland Yard said the Palace would be monitored by the Army as part of increased security measures after the terror alert in the country was raised to its highest "critical" level.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
About VDC
Doraiah Chowdary Vundavally is a Software engineer at VTech . He is the news editor of SocialNews.XYZ and Freelance writer-contributes Telugu and English Columns on Films, Politics, and Gossips. He is the primary contributor for South Cinema Section of SocialNews.XYZ. His mission is to help to develop SocialNews.XYZ into a News website that has no bias or judgement towards any.