CNN  — 

Three people were killed and five others were injured in a mass shooting Sunday evening at a restaurant near Phoenix, Glendale police said.

Officers responding around 7:45 p.m. to calls of a shooting found an “enormous scene,” said police in Glendale, Arizona. The city is about 10 miles northwest of downtown Phoenix.

“We’ve got multiple calls of a shooting that happened at an establishment,” police spokesperson Moroni Mendez said. “It was very chaotic.”

Police believe multiple shooters were involved. Several people have been detained for questioning, but no suspects have been taken into custody, Mendez said.

No officers or security personnel fired their guns, Mendez said. Police do not believe there is an ongoing threat to the public, he said.

It was among 97 mass shootings so far this year in the United States, with four or more people wounded or killed, not including shooters, according to Gun Violence Archive.

The events leading up to the Glendale shooting remain unclear, and police are asking people with information to come forward.

The five people injured were wounded by gunshots or shrapnel, Mendez noted. It’s unclear whether the victims knew one another, he added.

“We want to make sure we do a complete and thorough investigation and do right by the victims,” Mendez said.

“Obviously, they were involved because they were here tonight. Whether they know each other, whether they’re related, whether they’re allies or opponents – we don’t know yet, and that’s what we’re trying to solve and figure out,” Mendez said.

Bystander Lupe Rodriguez described the scene to CNN affiliate KPHO/KTVK.

“I heard people yelling out names. There was a man on the ground and it didn’t look like he made it,” Rodriguez said. “His father was yelling out his name. It was pretty bad.”

“It’s going to be several hours before this whole thing is cleared up,” Mendez said. “We’ll probably be working well into the daytime hours.”

This is a developing story and will be updated.