The suspect in the Golders Green double stabbing was referred to Prevent, the official counter-extremism scheme, in 2020.

The Guardian understands his case was closed within six weeks by the deradicalisation scheme, which has faced previous criticism.

The attack on Wednesday is being treated as terrorism by police who are investigating whether the suspect, who is in custody, was targeting people who were Jewish in the north-west London area.

Police say a 45-year-old man, a Somalia-born UK citizen, was arrested at the scene on suspicion of attempted murder.

In a statement counter-terrorism police said: “We can confirm the suspect was known to the Prevent programme and was subject to a Prevent referral in 2020, which was closed in the same year.

“Given the investigation remains ongoing, we will not be providing any further information in respect of this matter at this time and we remain focused on securing justice for the victims of this attack.”

The Met commissioner, Mark Rowley, has said the suspect has a history of violence and mental health issues.