GERMAN police said today that a Syrian asylum-seeker turned himself into custody, claiming responsibility for the Solingen knife attack last week that left three dead and eight wounded at a festival marking the city’s 650th anniversary.

Dusseldorf police said in a joint statement with the prosecutor’s office that the man “stated that he was responsible for the attack.”

“This person’s involvement in the crime is currently being intensively investigated,” the statement said.

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

The attack comes amid debate over immigration ahead of regional elections next Sunday in Germany’s Saxony and Thuringia regions where anti-immigration parties such as the populist Alternative for Germany are expected to do well. 

In June, Chancellor Olaf Scholz vowed that the country would start deporting criminals from Afghanistan and Syria again after a knife attack by an Afghan immigrant left one police officer dead and four more people injured.

Friday’s attack plunged the city of Solingen into shock and grief. A city of about 160,000 residents near the bigger cities of Cologne and Dusseldorf, Solingen was holding a Festival of Diversity to celebrate its anniversary.

The festival began on Friday and was supposed to run through to Sunday, but was cancelled because of the attack.

Officials had earlier said that a teenage boy was arrested on suspicion that he knew about the planned attack and failed to inform authorities, but that he was not the attacker. 

People alerted police on Friday morning that a man had assaulted several people with a knife on the city’s central square, the Fronhof.

Police said that the attacker appeared to have deliberately aimed for his victims’ throats.