A shooting at a Jehovah’s Witnesses hall in the German city of Hamburg killed eight people, apparently including the perpetrator, police said Friday. An unspecified number of other people were wounded, some of them seriously.

Police gave the figure on their website. There was still no word on a possible motive for the shooting on Thursday evening that stunned Germany’s second-biggest city. German Chancellor Olaf Scholz, a former Hamburg mayor, described the shooting as “a brutal act of violence.”

Investigators worked through the night to secure evidence. On Friday morning, forensic investigators in protective white suits could still be seen outside the building as a light snow fell. Officers placed yellow cones on the ground and windowsills to mark evidence.