Waco police have identified five different motorcycle gangs that were involved in the fatal shooting at a Twin Peaks restaurant that left nine dead.

Some of the gangs were allied, said Sgt. W. Patrick Swanton with Waco police. Others may have been there as a display of intimidation to show other gangs that they considered Waco their territory, he said.

>> UPDATE: Texas biker gang shooting: What you need to know now

Whatever the case, Waco police knew that the restaurant had become a powder keg for violent altercations between biker gangs. Police had arrested bikers there in previous incidents for fights, weapons charges and arrests, Swanton said.

As Sunday’s event at the restaurant neared, police renewed their pleas to Twin Peaks management to shut the event down, even going as far as to contact the restaurant’s national headquarters to see if they could pressure the Waco franchise to cancel its biker-related events.

Between 150 and 200 bikers packed the restaurant Sunday, crowding a full bar and patio area. About a dozen police officers, some of them SWAT officers, were in the immediate area to monitor the situation when a fight broke out inside the restaurant.

The fight spilled out into the parking lot, where it turned deadly.

Bikers shot and stabbed each other before turning their sights on officers as police moved in, Swanton said. Officers exchanged fire with bikers, but no police were injured. One officer was taken to a hospital for heat exhaustion, police said.

The fight also left 18 bikers injured with stab and gunshot wounds. Two with particularly serious injuries were taken out of the area, police said.

No bystanders were hurt, which Swanton said was largely due to police preparations that had officers already nearby when the fight broke out.

A Waco resident who arrived to the neighboring restaurant Don Carlos just minutes after the shooting described a chaotic scene in which officers were running around the area with guns drawn. Bethany Blattman arrived in the parking lot at about 12:20 p.m. with her mother, she said when reached by phone.

“There were just dozens and dozens of police cars,” Blattman said.

They managed to get into the parking lot, she said, but as they approached the restaurant, an officer carrying an assault rifle told them to leave.

“He said, ‘There’s a shooting going on and if you don’t want to be in the middle of it you should get somewhere else,’” Blattman said.

Waco police were in part blaming management of the Twin Peaks restaurant.

“In 34 years of law enforcement, this is the most violent crime scene I have ever seen,” Swanton said. “There are bodies still here.”

Swanton said managers at the restaurant were aware that tensions between biker gangs were building at the location. The restaurant was hosting a biker event where at least two gangs were using the restaurant as a place to recruit new members, Swanton said.

For more than a week, police had been aware of the event and had asked Twin Peaks management to shut it down in fears that it could turn violent. Those fears were confirmed Sunday when a fight that broke out in a restaurant bathroom spilled out into a bar area and then into the parking lot, Swanton said.

There it turned fatal. Nine are dead, and the death toll could rise, as 18 others are in hospitals, Swanton said.

Police combed through the crime scene, where Swanton said they found more than 100 weapons, including guns, knives and chains.

Police at the scene did fire upon bikers when weapons were pointed toward them. However, in the chaotic gun fight, it was unclear who shot whom, police said.

Law enforcement from the sheriff’s office, McLennan County, the FBI and surrounding communities have swarmed into Waco. The city was on full alert as rumors swirled of continued violence between gangs.

Swanton said police have intelligence that numerous bikers were on the way to the city. If seen, they would be arrested, he said.

Police have closed off the entire Central Texas Marketplace, the location of the Twin Peaks restaurant where the shooting occurred, stating that the area is not safe for anyone to enter. There were fears that members of rival biker gangs may come to the area, Waco station KCEN reported. Three people have been arrested while trying to enter the scene, police said.

The shooting also left 18 injured from gunshot and stab wounds, according to multiple reports. Eight people died at the scene and one died at a local hospital, according to the Associated Press. All nine fatalities were bikers, according to the KCEN report.