The Islamic State group has claimed responsibility for the knife attack in the German city of Solingen that killed three people.
The militant group said in a statement on its Telegram account the attack was carried out by one of its members "in revenge for Muslims in Palestine and everywhere".
It did not immediately provide any evidence for its assertion and it was not clear how close any relationship between the attacker and Islamic State was.
Eight more people were injured in the stabbing rampage at a music festival in Germany.
A 15-year-old has been detained after revellers were targeted at random at the three-day Festival of Diversity in Solingen near Dusseldorf on Friday evening and German Police have confirmed they made a second arrest.
Eight were injured, five of them seriously, the police said in a statement early on Saturday.
"Both victims and witnesses are currently being questioned. The police are currently searching for the perpetrator with a large team," police said.
The attack reportedly took place at around 9.45pm local time in the city's central square.
The knife-wielding perpetrator aimed specifically for the throats of his victims, the police added. They could not provide further details or a motive.
Fatal stabbings and shootings are relatively uncommon in Germany. The government wants to toughen rules on knives that can be carried in public by reducing the maximum length allowed.
In June, a 29-year-old policeman died after being stabbed in Mannheim during an attack on a right-wing demonstration. A stabbing attack on a train in 2021 injured several.
Friday's attack occurred at a festival marking the 650th anniversary of Solingen in North Rhine-Westphalia, Germany's most populous state, which borders the Netherlands.
Authorities cancelled the remainder of the weekend event.
The state's interior minister, Herbert Reul, visited the scene early on Saturday, telling reporters it was a targeted attack on human life but declining to speculate on the motive.
The attack occurred at the Fronhof, a market square where live bands were playing.
