Manchester Arena suicide bomber Salman Abedi should have been identified as a threat on the night of the attack by those in charge of security, a public inquiry into the May 2017 attack has found.

In his report examining security arrangements at the venue where 22 people were murdered and hundreds were injured at the end of an Ariana Grande concert, inquiry chairman Sir John Saunders found there were a number of missed opportunities to prevent or minimise the "devastating impact".

Sir John said he considered it likely Salman Abedi would still have detonated his device if confronted "but the loss of life and injury is highly likely to have been less.".

The report into the suicide bombing at the end of an Ariana Grande concert in May 2017 was published on Thursday afternoon.

Hearings at the public inquiry into the circumstances leading up to and surrounding the attack have been ongoing in the city since September last year.

Sir John Saunders, chairman of the Manchester Arena Inquiry, arrives at Manchester Magistrates Court ahead of the publication of the first volume of the Manchester Arena Inquiry report

Credit: Peter Byrne/PA

Inquiry chairman retired High Court judge Sir John Saunders issued his findings on a rolling basis, split into three volumes.

A further report will follow on the emergency response and the experience of each of those who died, and finally an analysis of whether the atrocity committed by Salman Abedi, 22, could have been prevented.

His first report to Home Secretary Priti Patel on the security arrangements within and outside the Arena was published at 2pm.

Manchester-born Abedi, of Libyan descent, walked across the City Room foyer of the venue towards the main doors and detonated his shrapnel-laden device, packed into his bulging rucksack, at 10.31pm on May 22 just as thousands, including many children, left the concert.

A further report will follow on whether the atrocity committed by Salman Abedi could have been prevented

The inquiry was told he made three reconnaissance trips to the venue, adjoining Manchester Victoria rail station, before his fateful last journey and security experts considered he may have noticed a CCTV blind spot on the raised mezzanine level of the City Room. Abedi, dressed in black, crouched down upstairs for nearly an hour, occasionally praying, before he walked down to the foyer.

A concerned Christopher Wild, waiting with his partner to pick up his daughter, earlier approached Abedi upstairs and said he asked him what was in his rucksack but he did not reply. When further pressed, Abedi told him he was "waiting for someone" and asked for the time.

Mr Wild thought "nervous" Abedi looked out of place and raised his concerns at about 10.15pm with Showsec steward Mohammed Agha, who was guarding an emergency exit, but told the inquiry he felt "fobbed off".

It was another eight minutes before Mr Agha relayed the concerns to colleague Kyle Lawler as the former had no radio to the security control room and did not believe he could leave his post, the inquiry heard.

Concerns were raised about Abedi with Showsec worker Mohammed Agha

Giving evidence, Mr Lawler said he had a "bad feeling" as he eyeballed Abedi but did not approach him as he did not think he had enough evidence and also feared being branded a racist.

He claimed he could not get through to the control room on his radio and agreed he simply "gave up" as he took up his position on a walkway bridge to the City Room.

Two independent security experts told the hearings they did not believe Mr Agha, then aged 19, and Mr Lawler, 18, at the time, were adequately supervised or trained.

Bosses at Manchester Arena said the exit doors to the foyer could have been closed within "a minute or two" if they thought it was necessary, the inquiry also heard. Security experts said "realistically" Abedi would still have detonated his bomb but there would have been fewer casualties.

The inquiry heard no-one from the venue operator SMG or its security provider Showsec checked the mezzanine level while Abedi was there after he earlier arrived at Victoria station at about 8.30pm, despite it being listed as an area for a "pre-egress check".

There were no uninformed police officers in the foyer of the arena when the bomb was detonated

Credit: Rui Vieira/AP

Uniformed officers from British Transport Police (BTP) were tasked to patrol the station, including the City Room, but when the bomb was detonated there were none in the foyer despite instructions that one officer should be positioned there at the end of the concert.

It also emerged two BTP officers took an "unacceptable" two-hour shift break, including a drive out to buy kebabs, with no officers on duty at the time Abedi, seen struggling to walk with his rucksack, made his "final approach" to take up position in the City Room.

On Thursday, Sir John is also expected to give his recommendations on the Government’s so-called Protect Duty, currently under consultation, which would make it a legal requirement for venues to protect people in public spaces.

The proposals build on Martyn’s Law, called for by Figen Murray, mother of Arena victim Martyn Hett, 29, which among other things is campaigning for venues and local authorities to have action plans against terror attacks.

Read: Manchester Arena bombing: The agonising missed chances to stop a killer