A gunman, believed to have been acting alone, killed several people in a Jehovah’s Witnesses church in Hamburg, Germany.
At the time of filing this report, German police were searching for a motive.
Police have also declined to say how many people were killed in Thursday night’s attack.
The gunman was believed to be among the dead.
Meanwhile, The Bild newspaper reported seven people were dead and eight wounded in the shooting in the northern city that is home to Germany’s biggest port.
The Jehovah’s Witnesses, on its part, said several of the wounded were seriously hurt.
No details of the suspected killer have been released.
Hamburg police were due to brief the media at noon (1100 GMT).
“Bad news from Hamburg,” Chancellor Olaf Scholz wrote on Twitter early on Friday, calling the attack “a brutal act of violence”.
He said his thoughts were with the victims, their families, and the security forces, who he said “have been through a difficult deployment” since the shooting at around 9 p.m. (2000 GMT).
Interior Minister Nancy Faeser said on Twitter that the authorities were working urgently to investigate the crime.
“We assume that there is one perpetrator,” police said late on Thursday. “Investigations into the motives behind the crime are continuing.”
Germany has some of the most stringent rules around gun control in Europe and the interior minister said late last year the government planned to tighten gun laws after a suspected plot by a far-right group to violently overthrow the state.
The Jehovah’s Witnesses said in a statement on their website that the religious community was “deeply affected by the horrific attack on its members of the faith in a Kingdom Hall in Hamburg after a service”.
The group expressed sympathy for the victims, families “and the traumatized eyewitnesses”. Ministers were “doing their best to support them in this difficult hour. We pray for all those affected and wish them the power of the God of all comfort”.
Police established an internet portal for people to upload photos and videos “of the crime or relevant events”.
Soon after the violence began, residents in the Alsterdorf district received warnings on their mobile phones of a “life-threatening situation” and the area was sealed off, the DPA news agency reported.
Television footage showed dozens of police cars as well as fire engines blocking off streets and some people, wrapped in blankets, being led by emergency service workers into a bus.
“We heard shots,” one unidentified witness told reporters.
“There were 12 continuous shots,” he said. “Then we saw how people were taken away in black bags.”
Police arrived at the scene to find several people seriously wounded and some dead.
“Then they heard a shot from above, they went upstairs and found one further person,” said a police spokesperson.
Germany has been shaken by a number of shootings in the last few years. In February 2020, a gunman with suspected far-right links shot dead nine people, including migrants from Turkey, in the western town of Hanau before killing himself and his mother.
In October 2019, a gunman killed two people when he opened fire outside a synagogue in the eastern city of Halle on the Jewish holy day of Yom Kippur.