LONDON: The Manchester Arena bomber may have been radicalized by a preacher who was known to authorities for more than a decade, the BBC reported.

Salman Abedi killed 23 concertgoers and injured more than 1,000 others in the 2017 suicide bombing after an Ariana Grande performance in Manchester.

A public inquiry into Abedi’s radicalization has found that Mansour Al-Anezi, a 43-year-old Kuwaiti national, had a close association with Abedi in the years leading up to the bombing, and was also linked to a failed terror attack years earlier.

The BBC reported that authorities in the UK were investigating Al-Anezi’s role as a suspected radicalizer after he was linked to Nicky Reilly, who, then aged 22, attempted to detonate a nail bomb in a restaurant in Exeter.

Reilly was jailed for the failed 2008 attack and died in prison in 2016.

However, the Manchester Arena inquiry has now linked Al-Anezi, who arrived in the UK in 2000, to both Reilly and Abedi, raising questions over the potential failure of authorities to prevent radicalization.

When Al-Anezi moved to Plymouth in the UK, his mosque preaching activities were monitored, with Britain’s domestic intelligence agency MI5 also collecting information on the preacher.

In the years leading up to the Exeter attack, Al-Anezi developed close links to Reilly, and authorities suspected the preacher of playing a major role in the 22-year-old’s radicalization.

Two sources from the mosque where Al-Anezi hosted prayers said that after the Exeter attack, the Kuwaiti national was banned from preaching, the BBC was told.

In an unrelated court case concerning Al-Anezi’s immigration status, the preacher admitted that some worshippers had expressed concern and complained about his activities.

However, authorities lacked the evidence to charge Al-Anezi in the aftermath of the attack.

As in the Exeter case, Al-Anezi also enjoyed close contact with the Manchester Arena bomber in the years leading up to the bombing, the BBC revealed.

He stayed at the Abedi home several times and regularly communicated with Abedi’s brother, Hashem, an associate in the attack, who was sentenced to life imprisonment for his role in the bombing.

When Al-Anezi died in 2017, Salman was reportedly “in tears,” with both brothers attending the preacher’s funeral.

However, the following day, the pair bought a substantial quantity of chemicals that would eventually be used to manufacture the bomb used in Manchester Arena, the BBC reported.

An asylum judgment dated to 2009 shows Al-Anezi’s admission that he entered the UK on a forged passport, with the government arguing that the preacher “wished to conceal information” and had “fabricated his claim for asylum.”

The Abedi inquiry will further examine the extent of Al-Anezi’s radicalization of the bomber.

A group of families whose relatives died in the bombing told the BBC that they were “disappointed to learn of yet more links to terrorism in Abedi’s background which do not appear to have been investigated.”

The families are relatives of Kelly Brewster, 32, Eilidh MacLeod, 14, Megan Hurley, 15, Liam Curry, 19, and Chloe Rutherford, 17, who were all killed in the blast.

The group said in a statement: “If there is enough information in the public domain for the press to make these links then we would have expected the government to do the same and investigate fully.

“We can only hope that this information was discussed in the closed hearings of the public inquiry.”

A Home Office spokesperson said: “Our thoughts remain with those who were killed or had their lives changed forever at the Manchester Arena attack.”