I would say that all of them were killed by the police. For two, actually three reasons: 1. No video of the incident has been released and the police always video their operations, from multiple angles when possible.2. No transcripts of 911 or any police radio traffic has been released. 3. The arrest of every witness and probably some who did not witness anything. The amount of bail they knew or believed that the arestees could not meet. And last but not least, they are being held incommunicado.
4. Two plus weeks later and they haven't released the ballistics report. It's way too late in the game if many or any were killed by bikers. We'll never know if any guns were dropped by LE as cover. No, I don't hate LEOs. I have Texas LEOs in the family and even they are questioning this.