Nine people were stabbed at the Swedish House Mafia concert in Dublin’s Phoenix Park reports BBC News. Two of them were seriously injured.

The incident occurred during the dance act’s headlining set. Police are investigating if more than one person was involved in the crime. But they have arrested a 23-year-old man who is currently in custody because of his possible ties with the stabbings.

Before the concert even started, ticket holders were subject to searches by security. “Ticket holders entering the site were subject to a search permissible by law,” concert promoters MCD said. “Every precaution… was taken to ensure the safety and security of the audience at all times.” The concert promoters have handed over CCTV footage on the grounds for police to further review.

The stabbings are not the end of this tragic story. BBC also reports that a 20-year-old attendee unexpectedly died “from a suspected drugs overdose.” He was taken to the hospital for medical attention, but later died. As of now, police are unsure as to what the motive was behind the stabbings and we expect more information to unfold.

[via BBC]