MMA star Conor McGregor attacks fellow fighter Will Fleury as he blames recent violence on 'revolving door immigration system with a gravy train on arrival'

The globally-renowned fighter was reacting to the rioting in Dublin on Thursday, which was sparked by a stabbing spree against children which hospitalised three youngsters (aged five and six) and a school assistant.

The perpetrator is rumoured to be a foreign national, purportedly from Algeria.

The street disorder which followed was blamed by Garda chief (and former PSNI officer) Drew Harris on “a complete lunatic hooligan faction driven by far-right ideology”.

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On Friday night, fellow MMA figure Will Fleury wrote on Twitter: “It’s sad to see the attack yesterday framed as an immigration issue when it clearly has a lot more to do with mental health and living in society so fractured nobody knew what this maniac was capable of until it was too late.”

Mr McGregor responded: “We know nothing of this man bar he is Algerian. What’s he here for? His mental health situation should not even be on our plate.

"It’s lax immigration first and foremost. And only.

"Take Josef Puska, 10-year invader of Ireland. Zero jobs attained. Full benefits claimed. Whole family housed. No language learned. Criminal background.

"Is this mental health? This is direct immigration policy/lack thereof.

"The mental health of these people is not and should not even be our problem.

"It is a revolving door immigration system with a gravy train on arrival that is the main cause of these current heinous crimes.”

Mr McGregor, who has investments in a number of businesses including the The Black Forge Inn pub in Dublin, also promised free service for life to a Brazilian immigrant – Ciao Benecio – who used a motorbike helmet to try and incapacitate the knife attacker, calling him “our Brazilian brother”.