The Islamic State group has issued an online message claiming a man who killed three people in a knife attack in western Germany was one of its members.

The Islamic State group has claimed responsibility for a knife attack in the German city of Solingen that killed three people and wounded eight others.

Police detained a teenager who may be connected with a knife attack but the perpetrator was still at large on Saturday.

Describing the man who carried out the attack as a “soldier of the Islamic State,” the militant group said in a statement on its Telegram account: “He carried out the attack 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 IS was.

Hendrik Wuest, premier of the state of North Rhine-Westphalia, described Friday evening’s attack during a festival in the city as an act of terror.

“This attack has struck at the heart of our country,” Wuest told reporters.

Police were conducting a manhunt for the assailant.

They said they had detained a 15-year-old and were investigating whether this person was linked to the attacker.

Dozens of police officers descended on a refugee shelter in Solingen on Saturday evening in an operation reportedly connected to the knife attack.

“We have received information and are currently carrying out police measures as a result,” a police spokesman said about the search.

A special task force was also deployed, and numerous police officers had cordoned off the area around the home for asylum seekers.

The attack took place in the Fronhof, a market square in the western German city where live bands were playing as part of a festival marking the its 650th anniversary.

Markus Caspers, an official with the public prosecutor’s office in Duesseldorf, said authorities were treating the attack as a possible terrorist incident because there was no other known motive and the victims seemed unrelated.

Police official Thorsten Fleiss said the assailant appeared to aim for his victims’ throats.

“The perpetrator must be quickly caught and punished to the fullest extent of the law,” Chancellor Olaf Scholz said in a post on X.

Police cordoned off the square on Saturday and passers-by placed candles and flowers outside the barriers.

“We are full of shock and grief,” Solingen mayor Tim-Oliver Kurzbach told reporters.

A German musician who goes by the name Topic said he was playing on a nearby stage when the incident occurred.

He was told about what had happened but was asked to keep playing “to avoid causing a mass panic attack,” he posted on Instagram.

He was eventually told to stop, and “since the attacker was still on the run, we hid in a nearby store while police helicopters circled above us,” Topic wrote.

Authorities cancelled the remainder of the weekend festival.

North Rhine-Westphalia Interior Minister Herbert Reul visited the scene early on Saturday.

He told reporters it was a targeted attack on human life but declined to speculate on the motive.

Solingen, well known for its knife manufacturing industry, is a city of about 165,000 people.

—AAP