A person armed with a knife killed at least three people at a city fair in the western German city of Solingen on Friday night, according to the police. The attacker, who escaped, also severely wounded five others. Officers were looking for a suspect.

Local news outlets reported that a lone attacker had turned on the crowds during the fair celebrating the 650th anniversary of the city’s founding.

“This evening, we are all in shock, horror and great sadness in Solingen,” Tim Kurzbach, the city’s mayor, said in a post on Facebook. “We all wanted to celebrate our city’s anniversary together and now we have to mourn the dead and injured.”

So far, the motive for the attack is unclear.

The police were interviewing witnesses and those victims able to talk for details that could help catch the attacker, a Düsseldorf police spokesman said on Saturday morning.

The attack took place in a central square in Solingen, which is about 14 miles east of Düsseldorf, where the city fair, which attracted thousands, was underway.

The area quickly emptied of visitors, as the police tried to catch the assailant and set up barriers, news outlets reported. Videos from the scene showed a strong police presence. And some local officials visited the site early Saturday morning.

The Associated Press reported that the city canceled the rest of the festival after the attack.

The attack comes nearly three months after a police officer was killed in a knife attack in Mannheim 130 miles south. In that attack, six people, including the officer, were stabbed at anti-Islamist rally.