Waco Police Sgt. Patrick Swanton says they now believe the ordeal started with a planned meeting between several motorcycle groups in the outdoor bar area.
"We know an additional biker gang that was not invited to this meeting showed up. Hence what we were calling somewhat of a turf war if you will," Swanton said.
Court paperwork says the Bandidos and Cossacks are groups recognized by DPS as criminal street gangs.
Swanton says investigators believe the altercation started in the parking lot...possibly with someone's foot being run over...and it spread from there.
"Those crime scenes include bathroom areas, the restaurant areas and the bar areas," Swanton said.
Swanton says the investigation may take weeks, even months. He says it's a lengthy process when some of those arrested aren't being truthful.
Waco Police say the McLennan County Jail had plenty of room for the 170 people they arrested in connection with the shooting. But jail staff were called in to book and process them through the night. One of those detainees is a City of Austin Public Works employee.
Austin Public Works says 36-year-old Juan Garcia is an engineer for the department. He's currently on leave.
As far as threats to law enforcement, Swanton says they have been very real and credible but those threats have toned down over the last 24 hours.
He's asking biker gangs to stand down.
"There has been enough tragedy and there's been enough bloodshed in Waco Texas. We would appreciate there not being any more," Swanton said.
Swanton says of the 18 injured and taken to local hospitals, 7 remain...stable and improving.
In the meantime, the Texas Rangers and DPS are investigating as well. They say more arrests may be on the way.
FOX 7 is digging deep into who these bike gang members really are.
Four of them are from Austin, including Garcia.
The 9 bikers who passed away were from all over the state.
Most of them didn't have previous criminal history. Three of them had charges ranging from DWI's to unlawful carrying of a weapon.
They ranged in age from 27 to 65.
Autopsy reports show that they all died from gunshot wounds to the head and upper body.