A man who lost his brother in the Manchester Arena attack has said that “assigning blame is a mug’s game” after an official review into the terror attack revealed that it might have been averted.

Dan Hett lost his 22-year-old brother Martyn when terrorists targeted an Ariana Grande concert on May 22.

A report by David Anderson QC, released on Tuesday, established that bomber Salman Abedi was a former “subject of interest”, adding that it was “conceivable” the attack “might have been averted had the cards fallen differently”.

The report examined the way police and the security services handled intelligence before four terrorist attacks hit London and Manchester earlier this year.

Adebi was twice a “subject of interest” to MI5 in the year before the attack but investigations were closed and the threat Abedi posed was downgraded, the report said.

Hett explained how he felt about the report, admitting it was a very difficult story to read, but adding that hindsight was an “easy thing to fall back on”.

unsure where I stand on this. this was a fucking hard story to read, make no mistake, but people are painting these decisions as straight-up mistakes, and that feels like an oversimplification. /1 https://t.co/Qa0udYqLBC

December 5, 2017
“had the cards fallen differently” – hard as it is to imagine this falling differently, I can’t fathom how complicated modern antiterrorism intelligence is. hindsight is an easy thing to fall back on. /2

December 5, 2017
the headlines paint a fairly slanted assessment that at a glance implies mistakes, and this definitely doesn’t sit okay. as usual, outraged armchair experts come out of the woodwork to criticise. /3

December 5, 2017
tellingly, the positive aspects (I know, I know) around successful work are only footnotes in most articles about this. this isn’t black and white, none of this is, ever. /4

December 5, 2017
and of course, the commentary that will pop out from our gutter press and the usual unqualified twitter gobshites (you know who you are) will distort this further still. don’t be suckered in. /5

December 5, 2017
the cards didn’t fall differently, for more reasons than any of us could possibly fathom. use hindsight if it can improve the future, but assigning blame is a mug’s game. out. /6

December 5, 2017
Anderson found that three of the six terrorists involved in the Manchester and London attacks – which claimed more than 30 lives between March and June – were on the security services’ radar.

Abedi detonated a shrapnel-laded homemade bomb as people were leaving Manchester Arena after an Ariana Grande concert, resulting in the deaths of 22 people and causing injuries to a further 500.

Adebi was twice a “subject of interest” to MI5 in the year before the attack but investigations were closed and the threat Abedi posed was downgraded, the report said.

Fresh intelligence was also received in the months before the 22-year-old’s suicide bombing, but its “significance was not fully appreciated at the time”.

“In retrospect, the intelligence can be seen to have been highly relevant to the planned attack,” the report found.

It revealed that an MI5 meeting due to discuss Abedi, a Briton born to Libyan parents, was scheduled for 31 May – nine days after the bombing.

It is not the first time that Martyn’s family has spoken out since the terror attack.

His mother, Figen Murray, was commended last week for her “dignified and heartfelt” response to US President Donald Trump after he retweeted propaganda videos from far-right British group, Britain First.

Anderson reviewed reports into the attacks at Westminster Bridge on March 22, the Manchester Arena bombing, the London Bridge attack on June 3 and the incident at Finsbury Park Mosque on June 19.

Responding to the report, Andrew Parker, the director general of MI5, said the intelligence service is facing an “unprecedented threat from international terrorism” and will continue to “adapt and change to keep pace with a fast-moving world”.

Cressida Dick, commissioner of the Metropolitan Police Service, said: “Policing and our colleagues in the fight against terrorism will continue to learn and improve.

“We need to make rapid progress in implementing the recommendations, many of which require new technology, better infrastructures and resources at a time when the threat from terrorism poses significant challenges for police and security services.

“The growth in the number of dangerous individuals who have been radicalised is a major issue for us. We will be redoubling our efforts in enforcement activity both to disrupt and confront the threat and to safeguard the vulnerable from radicalisation.”