Police are to be investigated into the handling of London Bridge attacker Usman Khan's prison release.
The Independent Office for Police Conduct (IOPC) had already begun an investigation into the fatal shooting of Khan by Metropolitan and City of London Police officers, which is standard for such incidents.
But the watchdog has now launched a separate investigation after they received a referral from Staffordshire Police relating to its contact with the convicted terrorist, who was living in Stafford, prior to the attack.
After requesting further information from the force, the public body said it had concluded that a separate independent investigation should be conducted.
A statement released by the IOPC on Thursday said the investigation was "still in its very early stages".
Sal Naseem, IOPC director of London, said: "Our separate investigation into the decisions and actions of Staffordshire Police has just begun and will be conducted alongside the investigation into the shooting."
Cambridge Unviersity graduates Jack Merritt, 25, and Saskia Jones, 23, were killed by Khan during a prisoner rehabilitation event at London Bridge's Fishmongers' Hall on November 29.
Khan, who was armed with two knives and wearing a fake suicide vest, was tackled by members of the public, including ex-offenders from the conference, before he was shot dead by police.
It later emerged that Khan was released from prison on licence in December 2018, halfway through a 16-year prison sentence, after he was convicted of terror offences in February 2012.
The attack has prompted the Ministry of Justice to review the licence conditions of every convicted terrorist released from prison.
The IOPC said it began its investigation into the fatal shooting by officers immediately after the incident.
