The British Security Service (MI5) has prevented nine terror attacks this year but failed to stop five, including the Manchester Arena terror attack, with an internal review saying the plot could have been stopped.

MI5 chief Andrew Parker, told Downing Street that since the murder of Fusilier Lee Rigby in 2013 by two Islamic extremists, 22 terror plots have been foiled.

However, an internal review has found that one of the five plots successfully executed this year, the Manchester Arena terror bombing, could have been stopped.

Author of the review David Anderson QC said it was possible the attack by Salman Abedi, the son of an Islamic radical refugee from Libya, could have been avoided had the “cards fallen differently”.

Abedi killed 22 people — mostly women and children — at an Ariana Grande concert in May.

An unclassified version of the review outlines that Abedi had been a “subject of interest” (i.e., under investigation) to MI5 between January and July 2014 and again in October 2015.

The Islamist fighters who fought for MI5 in foreign wars without even realising it https://t.co/Jhqije6AIZ — Breitbart London (@BreitbartLondon) May 27, 2017

MI5 also received relevant intelligence on two separate occasions in the months before the attack, which the report noted: “In retrospect, the intelligence can be seen to have been highly relevant to the planned attack.”

The domestic security agency also missed an opportunity to place Abedi on entry ports notification following his travel to Libya in April 2017, despite his status as a “closed SOI” (one of 20,000 people who have been part of MI5 Priority Investigations since 2009 “but who have been given a holding code which indicates that they are no longer assessed to represent a national security threat”).

However, the review said it was “unknowable” whether reopening investigations into Abedi would have stopped his plans, with Mr. Anderson adding: “MI5 assesses that it would not.”

The document also revealed that Khuram Butt, the leader of the London Bridge and Borough Market attack, and Khalid Masood, who targeted Westminster Bridge, had also been on MI5’s radar prior to their attacks.

23,000 Jihadists, the vast majority of whom MI5 and the Police don't have the time, money, or people to watch https://t.co/goUgrrIa73 — Breitbart London (@BreitbartLondon) May 27, 2017

In a House of Commons statement on Tuesday, Home Secretary Amber Rudd said that based on police and MI5 reviews, “neither MI5 nor the police had any reason to anticipate the [Westminster Bridge] attack” and likewise “a number of different investigative means were deployed against [Butt], but they did not reveal his plans”.

She added: “MI5 and Counter-Terrorism Policing are currently running well over 500 live operations – a third up since the beginning of the year – involving roughly 3,000 ‘subjects of interest’. In addition, there are over 20,000 further individuals – or closed subjects of interest – who have previously been investigated, and may again pose a threat.”

Robust words from the former COBRA committee member and Afghan task force commander https://t.co/y2zBDfhlIo — Breitbart London (@BreitbartLondon) May 27, 2017

UKIP’s Security spokesman Richard Bingley said the review highlights the need to prosecute all returning jihadists and for minimum sentences for terrorism offences to be significantly increased. He also asserted that the Terrorism Act “is not fit for purpose”.

“A new Prevention of Terrorism Act is required in order to make explicit the prioritisation of public safety over individuals actively supporting or conducting mass casualty attacks,” Mr. Bingley said in a press release.

“Furthermore, the irresponsible cuts to our police, border controls, CPS, paramedics, and armed forces require total reversal. Other countries such as the USA and France are resourcing up.”

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