ORF has not stated the ideology of the attackers. GB where did you get right wing? Generally in Spain it is either Muslim or Basque. Right wing is usually Madrid
Spanish Police have identified one of the attackers as a North African - Spanish police have released a photograph of the man alleged to have rented the van used in the attack. He is identified as Driss Oukabir.
Separate reports said the Guardia Civil have identified the suspect thought to have hired the white Fiat van used in the attack. According to those reports, he is understood to be from north Africa but to possess an NIE, the identity document issued to foreigners who are resident in Spain.
I have never seen a Muslim Identified as right wing
They are hold up in a Bar real close to the Hotel Royal and the Marriott. Maybe they were pissed off at the high prices for faux tapas and the Burgers in the Marriott.