First came a few pistol shots, several witnesses said, then a barrage of rifle fire during the shootout last month at a Waco restaurant favored by bikers. But authorities still have not said how many of the dead and wounded were the result of police fire.

Police have identified only one assault weapon, a semi-automatic gun that fires high-powered ammunition, among the firearms confiscated from bikers, and that was found in a locked car after the shooting ended. But several witnesses — at least three of them veterans with weapons training — told The Associated Press that semi-automatic gunfire dominated the May 17 shootout that left nine dead and 18 wounded.

"I heard, 'pop, pop,' small caliber, and then a rapid succession of shots from what sounded to me like an assault rifle," said William English, a former Marine and Iraq war veteran who was approaching the front door of the Twin Peaks restaurant for a meeting of biker clubs.

It's remains unclear exactly what triggered the gunfight. More than 100 of the 170 people arrested, mostly bikers and family and friends, are still in custody and cannot give their accounts. Six witnesses interviewed by the AP describe a melee that began with a few pistol shots but was dominated by semi-automatic gunfire.

Waco police have said they returned fire after being shot at, and call the witnesses' depictions of events incorrect. While those with pending charges may benefit by blaming authorities, police have declined to release detailed reports from that day and say they are still awaiting ballistic reports.

English said shots came from the restaurant's patio as he and his wife approached the building. They and other members of their Distorted motorcycle club took cover on the opposite side of the patio.

Steve Cochran, a Navy veteran and member of the Sons of the South club, pulled into the parking lot facing the patio minutes before the shooting began. He was to help set up for the meeting of the Confederation of Clubs and Independents, a group that advocates for biker rights and motorcycle safety.

"I heard one pistol shot. All the rest of the shots I heard were assault rifles," said Cochran, who took cover behind a crane about 30 yards away. He walked the shooting scene with the AP several days later, showing what he saw and his vantage point.

Cochran said he heard suppressed rounds fired by assault weapons, which are still audible but sound different than a handgun firing.

Police have said 18 officers, four state troopers and more than 200 bikers were at Twin Peaks at the time. Investigators have said the shooting began during an apparent confrontation between the Bandidos, the predominant motorcycle club in Texas, and the Cossacks, and it then spilled into the parking lot. Video viewed by the AP indicated that the fight began outside.

Ron Blackett, a Confederation of Clubs and Independents leader who is a former Army and Coast Guard officer, also reported hearing one or two pistol shots followed by a blast of assault rifle fire from where he was parked in a lot behind Twin Peaks.

According to some records released to the AP following a public information request for 911 calls, Officer Brandon Blasingame reported "shots fired," to a dispatcher at 12:26 p.m.

"Two shot behind Twin Peaks," Blasingame reported two minutes later.

"They have an AR-15," he said in the next dispatch. It was unclear who he meant had the rifle, and if it was something he saw or was told.

The chronology ends at 12:31 p.m. and police have refused to release the rest of the report, saying it could compromise the investigation. Blasingame did not respond to requests for comment.

Waco police spokesman Sgt. W. Patrick Swanton says the witnesses' depictions of events are "absolutely incorrect," asserting that police shot fewer rounds than the bikers. He confirmed that some officers carry semi-automatic weapons, which fire a single shot with every pull of the trigger, and automatically reload between shots.

Jennifer Cicolani, of the Bureau of Alcohol, Tobacco, Firearms and Explosives, noted that a semi-automatic gun can shoot more bullets in less time than a small-caliber weapon.

Swanton declined to say whether assault weapons beyond the AK-47 in the car had been seized, reiterating that 318 weapons were collected, including that gun, handguns, brass knuckles, knives and chains.

Waco police have sent the weapons to a ballistics lab in Washington, D.C., and say it could take months to get results to show which bullets struck the dead and injured.

After the melee, police records show officers rounded up anyone suspected of being part of a biker gang, targeting those in leather vests and patches. Neither Blackett nor Cochran was arrested. English and his wife were, and were held for more than two weeks before being released on $25,000 bail.

"One of the sheriff's officers said we were going to be interviewed and turned loose," said English, who was wearing a leather vest that day with the name of his club on it.

Nearly all of those arrested were charged with engaging in organized crime, a felony. About 60 people had bonded out by Thursday, but those with the closest views of the shooting remain in jail and cannot talk, say the bikers' attorneys.

A biker rally to support those still in jail is planned for Sunday in Waco.