As reported by The Hill on Monday, the FBI previously informed UK intelligence service MI5 about Salman Abedi, the 22-year-old Manchester bomber who detonated himself in the lobby of a performance venue on May 22 following a pop concert, killing 22 — including many children — and injuring 116.
According to reports, the FBI detailed to MI5 last January that Abedi was a member of a Daesh-affiliated group and was plotting a terrorist attack in the UK.
"I think it's right that MI5 takes a look to find out what the facts are. We shouldn't rush to make any conclusions at this stage," stated British Home Secretary Amber Rudd on Monday, according to the the BBC).
Some 16 arrests have been made in connection with the ongoing investigation into the suicide bombing. A 23-year-old pilot in training was arrested on Monday in the south of London as operations continue.
Additional information has revealed that, prior to the bombing, two people familiar with Abedi separately contacted the police warning of his extremist views, the BBC reports.
While a teenager, Abedi was reportedly associated with an armed insurgency against former Libyan dictator Moammar Gadhafi, and worked with extremist militants in the northern African country during school holidays.
Reuters cited an undisclosed source close to UK intelligence stating, "This is a review that would seek to answer whether there are lessons to be learned from how the security service handled the intelligence on Abedi."
The UK government has notched its threat level down from "critical" — the highest level — to "severe," and security remains high at public gatherings, including yesterday's Great Manchester Run, attended by an estimated 40,000 participants.
Rudd, when asked about how many people were thought to be at risk of terror activity in the UK, answered that, in the "top list," some 500 potential plots involving 3,000 people were currently being tracked, as well as an additional 20,000 people with possible connections to terrorism.