Several pupils were injured in an attack at a school in the western German city of Wuppertal on Thursday, police said, with local media reporting that the assailant was a knife-wielding fellow student.

A suspect had been taken into custody following the attack, police said, without confirming the person's identity or the weapon used.

"We are on site with a large number of officers. There are injured school children," Wuppertal police said on X, formerly Twitter.

No exact number of pupils injured was immediately provided but police told local paper Wuppertaler Rundschau that it remained in "single digits". 

Local media reported the suspect had attacked pupils at the school with a knife.

The alleged attacker was a pupil at the school, according to German daily Bild.