Man arrested near UK PM's residence in terrorism probe

A man carrying knives has been arrested close to the official London residence of the British prime minister, as police said they suspected he was preparing an "act of terrorism".

Police said a man in his late 20s was arrested under the Terrorism Act by armed officers outside Downing Street on Thursday afternoon.

Security in the area has been heightened in recent weeks since five people were killed by an attacker who drove a car into pedestrians on Westminster bridge, and then stabbed a police officer at the entrance to the nearby Houses of Parliament before being shot dead by police.

Police said no one had been injured in the incident on Thursday. A Reuters photographer claimed to have seen at least three knives on the ground.

The police said in a statement: "A man has been arrested in Whitehall this afternoon, at approximately 2.22pm, following a stop and search as part of an ongoing operation.

"The man was arrested in Parliament Street, junction with Parliament Square, by armed officers from the Met’s Specialist Firearms Command.

"The man, aged in his late 20s, was arrested on suspicion of possession of an offensive weapon and on suspicion of the commission, preparation and instigation of acts of terrorism.

"Knives have been recovered from him.

"He is being detained under the Terrorism Act and is in custody in a south London police station.

"Detectives from the Counter Terrorism Command are continuing their investigation, and as a result of this arrest there is no immediate known threat."

British Prime Minister Theresa May was not at Downing Street at the time of the incident, her spokesman said.

Reuters pictures showed police officers standing by at least two knives lying on the ground.

Armed officers sealed off the area. A Reuters reporter and photographer saw police holding a dark-skinned, bearded man dressed in a hooded, black coat.