"...Vehren said police were alerted to the shooting about 9:15 p.m. and were on the scene quickly. He said that after officers arrived and found people with apparent gunshot wounds on the ground floor, they heard a shot from an upper floor and found a fatally wounded person upstairs who may have been a shooter. He said police did not have to use their firearms.
Vehren said there was no indication that a shooter was on the run and that it appeared likely that the perpetrator was either in the building or among the dead. "
https://www.cbsnews.com/news/hamburg-germany-shooting-jehovahs-witness-hall-gross-borstel/