Police standards investigators are looking into a crash involving a police van and a Porsche in Totteridge that left two officers in hospital.
The van flipped onto its side in the collision with the 911 Boxster in Totteridge Lane shortly before 2.15pm on Wednesday.
The Metropolitan Police says the incident has now been referred to its Directorate of Professional Standards, which investigates standards of police conduct.
Yesterday the force confirmed the van was responding to a 999 call and was on its way to a domestic incident in Barnet when it was involved in the collision.
Two police officers who were travelling in the van were taken to hospital with minor injuries and have since been discharged.
The man driving the Porsche was treated for shock at the scene.