HAMBURG, Germany — A gunman stormed a service at his former Jehovah’s Witnesses congregation in Hamburg, killing six people before taking his own life after police arrived, authorities in the German port city said Friday.

Police gave no motive for Thursday night’s attack. But they acknowledged recently receiving an anonymous tip that claimed the man identified as the shooter showed anger toward Jehovah's Witnesses and might be psychologically unfit to own a gun.

Eight people were wounded, including a woman who was 28 weeks pregnant and lost the baby. Chancellor Olaf Scholz said the death toll could rise.

Officers apparently reached the hall , a boxy building next to an auto repair shop a few kilometers (miles) from downtown, while the attack was ongoing — and heard one more shot after they arrived, according to witnesses and authorities. They did not fire their weapons, but officials said their intervention likely prevented further loss of life.

Scholz, a former Hamburg mayor, lamented the “terrible incident in my home city.”

“We are speechless in view of this violence,” Scholz said at an event in Munich. “We are mourning those whose lives were taken so brutally.”

All of the victims were German citizens apart from two wounded women, one with Ugandan citizenship and one with Ukrainian.

Officials said the suspected gunman was a 35-year-old German national identified only as Philipp F., in line with the country's privacy rules. Police said he had left the congregation “voluntarily, but apparently not on good terms,” about a year and a half ago.

A website registered in the name of someone who fits the police description of the suspected gunman says that he grew up in the Bavarian town of Kempten in “a strict religious evangelical household.”

The website, which is filled with business jargon, also links to a self-published book about “God, Jesus Christ and Satan.”

Philipp F. legally owned a semi-automatic Heckler & Koch Pistole P30 handgun, according to police. He fired more than 100 shots during the attack — and the head of the Hamburg prosecutors office, Ralf Peter Anders, said hundreds more rounds were found in a search of the man’s apartment.

Germany’s gun laws are more restrictive than those in the United States, but permissive compared with some European neighbors, and shootings are not unheard of.

Last year, an 18-year-old man opened fire in a packed lecture at Heidelberg University , killing one person and wounding three others before killing himself. In 2020, there were two high-profile shootings, one in which six people were killed and another in which nine people died .

In the most recent shooting involving a site of worship, a far-right extremist attempted to force his way into a synagogue in Halle on the Jewish holy day of Yom Kippur in 2019 . After failing to gain entry, he shot two people to death nearby.

The German government announced plans last year to crack down on gun ownership by suspected extremists and to tighten background checks. Currently, anyone wanting to acquire a firearm must show that they are suited to do so, including by proving that they require a gun. Reasons can include being part of a sports shooting club or being a hunter.

Hamburg police chief Ralf Martin Meyer said the man was visited by police after they received an anonymous tip in January, claiming he “bore particular anger toward religious believers, in particular toward Jehovah’s Witnesses and his former employer.”

Officers said the man was cooperative and found no grounds to take away his weapon, according to Meyer.

“The bottom line is that an anonymous tip in which someone says they’re worried a person might have a psychological illness, isn’t in itself a basis for (such) measures,” he said.

On Friday morning, forensic investigators in protective white suits could be seen outside the Jehovah’s Witnesses Kingdom Hall. As a light snow fell, officers placed yellow cones on the ground and windowsills to mark evidence.

Hamburg’s top security official said a special operations unit that happened to be near the hall arrived just minutes after receiving the first emergency call at 9:04 p.m. The officers were able to separate the gunman from the congregation.

“We can assume that they saved many people’s lives this way,” Hamburg state Interior Minister Andy Grote told reporters.

Upon arrival, officers found people with apparent gunshot wounds on the ground floor, and then heard a shot from an upper floor, where they found a fatally wounded person believed to be the shooter, according to police spokesman Holger Vehren. They did not fire their weapons.

Student Laura Bauch, who lives nearby, said there were around four periods of shooting, German news agency dpa reported. “There were always several shots in these periods,” she said.

Bauch said she looked out her window and saw a person running from the ground floor to the second floor of the Jehovah’s Witnesses hall.

Gregor Miebach, who lives within sight of the building, heard shots and filmed a figure entering the building through a window. In his footage, shots can then be heard from inside. The figure later apparently emerges from the hall, is seen in the courtyard and then fires more shots through a first floor window before the lights in the room go out.

Miebach told German television news agency NonstopNews that he heard at least 25 shots. After police arrived, one last shot followed, he said.

His mother, Dorte Miebach, said she was shocked by the shooting. “It's really 50 meters (yards) from our house and many people died,” she said. "This is still incomprehensible. We still haven't quite come to terms with it.

Jehovah’s Witnesses are part of an international church, founded in the United States in the 19th century and headquartered in Warwick, New York. It claims a worldwide membership of about 8.7 million, with about 170,000 in Germany.

Members are known for their evangelistic efforts that include knocking on doors and distributing literature in public squares. The denomination’s practices include a refusal to bear arms, receive blood transfusions, salute a national flag or participate in secular government.

David Semonian, a U.S.-based spokesman for Jehovah’s Witnesses, said in an emailed statement early Friday that members “worldwide grieve for the victims of this traumatic event.”

“The congregation elders in the local area are providing pastoral care for those affected by the event,” he wrote.

By Friday afternoon, the bodies of the victims had been removed from the hall, and residents laid flowers outside to commemorate the victims.