Video posted to social media showed a bearded man in glasses attacking attendees of an event staged in the city’s Marktplatz square by the anti-Islam Pax Europa Citizens’ Movement. The footage appears to show one person stabbed in the leg while a police officer who attempted to intervene apparently suffered a neck injury. The attacker was then shot by a second police officer.

"A firearm was used against the attacker," Mannheim police said.

The incident occurred as Michael Stuerzenberger, an anti-Islam activist, prepared to address a small crowd, Reuters reported.

No information was available on the attacker’s identity or motive and Mannheim police declined to provide details about the condition of the attacker’s victims.

Interior Minister Nancy Faeser wrote in a social media post: "My thoughts are especially with the seriously injured police officer."

She continued: "If investigations show an Islamist motive behind the attack, that would be yet another confirmation of the great danger posed by Islamist violence, which we have been warning about."

"The attacker must be punished severely," Chancellor Olaf Scholz posted.

The attack occurred during campaigning for European elections, during which the far-right Alternative for Germany (AfD) party has stressed the security risks associated with immigration from Muslim countries.

Local police said there was no longer any danger to the public.