SOLINGEN, Germany (AP) — German police said early Sunday that a 26-year-old man turned himself in, claiming to be behind the deadly Solingen knife attack that left three dead and eight wounded at a festival marking the city’s 650th anniversary. Düsseldorf police said in a joint statement with the prosecutor’s office that the man “stated that he was responsible for the attack,” adding he had been arrested before, but didn’t provide details. “This person’s involvement in the crime is currently being intensively investigated,” the statement said.

On Saturday the Islamic State militant group claimed responsibility for the attack, without providing evidence. The extremist group said on its news site that the attacker targeted Christians and that he carried out the assaults Friday night “to avenge Muslims in Palestine and everywhere.” The claim couldn’t be independently verified.

Officials had earlier said a 15-year-old boy was arrested on suspicion he knew about the planned attack and failed to inform authorities, but that he was not the attacker. Two female witnesses told police they overheard the boy and an unknown person before the attack speaking about intentions that corresponded to the bloodshed, officials said. RELATED COVERAGE Romanian authorities tow luxury vehicles from Andrew Tate’s home after new human trafficking allegations Hundreds of police raid a religious compound in search of Filipino preacher wanted for child abuse Islamic State grou.