We're learning more about the circumstances around Sunday's gunfight between rival biker gangs in Waco, Texas, that left nine people dead and sent 18 to the hospital. At least 170 people were arrested after the fracas broke out at a Twin Peaks restaurant.

The names of the slain bikers haven't been released, says Sgt. Patrick Swanton of the Waco Police Department, because police are still working to notify their next-of-kin. He added, "We're having issues doing that."

At a midmorning news conference, Swanton said police are having trouble getting in touch with family members because some of the people involved are not being honest with police.

Giving an update on the 18 people who went to hospitals, Swanton said that seven remain there — and that "all are stable and most are improving."

Dismissing media reports that law enforcement officers had killed four bikers, Swanton said, "whoever told you that, that person belongs on CSI, because the autopsies haven't been completed."

Swanton also gave more details about the scene at the restaurant and the dozens of bikers who were there.

"Many of them were not from the local Waco community," he said.

"There was a planned meeting of one group of biker members," Swanton said, comprising a coalition of invited gangs.

"We know an additional biker gang that was not invited to this meeting showed up," Swanton said, sparking what he called "a turf war."

Responding to a question later, Swanton said police officers had not been posted inside the restaurant because the business did not welcome their presence. As we reported Monday, Twin Peaks Restaurants is revoking the franchise agreement with the Waco location.

He summarized Sunday's events:

Investigators have been going over the crime scenes and recovering evidence; Swanton said that a flat-bed truck loaded with motorcycles had left the restaurant's property under heavy escort.

Some 135 motorcycles need to be removed from the crime scene, he said, along with "at least 80 cars and pickups" that could contain evidence and must be removed.

On Monday, Waco's police department said the "scene is littered with bullets, blood and other evidence. Civilian as well as Police units with bullet holes remain to be processed."

The police officers who were involved in the shooting haven't been removed from active duty, as is customary, "because of the high threat level" in Waco, Swanton said.

There were 18 Waco police officers on the scene Sunday — Swanton says all were involved, even if not all of them fired their weapons. He later said it was likely that three or four of the officers had fired their guns.

Of the potential for more trouble on the Memorial Day weekend, Swanton said, "We hope it goes back to that normal traffic-crash type of situation that we have to deal with."

Noting the tendency among biker gangs for violence to spark more fighting, Swanton said: "Is this over? Most likely not."

"There have been credible, reliable threats against our officers" that have "been toned down" somewhat in the past 24 hours, he said. Swanton added, "We appreciate that."

He confirmed that more bikers were seen arriving in the area after the shootout, but he added that has also seemed to drop off.

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