Two men accused of butchering a British soldier had been part of previous investigations by security services, a British official said Thursday, as investigators searched several locations and tried to determine whether the men were part of a wider plot to instill terror on the streets of London.
On Thursday, Scotland Yard said counterterrorism officers arrested two more people, a man and a woman — both 29 — on suspicion of conspiracy to murder. Both suspects are in custody at a south London police station.
Both suspects in the London attacks had been part of previous terror investigations by Britain's security services, according to a British official who spoke to The Associated Press on condition of anonymity because he was not authorized to speak about the police inquiry and cautioned that details could jeopardize future trials.
It was unclear how recent the investigations were or whether the men were loosely tied to other suspects being investigated or whether they themselves had been put under surveillance, which could have included being watched by undercover investigators or having their phone calls and emails intercepted.