Police in Waco were monitoring reports Tuesday that more motorcycle gang members could be headed for the Texas city where a gunfight last weekend between dueling gangs left 9 people dead and 170 possibly facing murder charges -- all reportedly over a disputed parking space.

The Dallas Morning News reported that police were pursuing the parking space theory after interviewing several witnesses to the deadly melee Sunday that also injured 18. Another 170 gang members were charged with organized crime activity Monday. Bond was set at $1 million for each suspect, and the Morning News reported that members of each gang being kept separate from the other gangs at the local jail. 

As a press conference Tuesday morning, Waco authorities urged gangs to "stand down" and end the violence. 

Authorities remained on alert Tuesday after receiving what they called "credible information" that members of other motorcycle gangs might be heading to Waco to attack law enforcement officers in retaliation for Sunday's violence. Members of tactical units from various law enforcement agencies, including the FBI, stood guard over the crime scene outside the Twin Peaks restaurant, while snipers stood on the roof.

Sgt. Patrick Swanton told reporters that a gang member's foot was "run over" in the parking lot Sunday, which he said ignited the situation. He also said one of the five biker gangs was not invited to the meeting and described the melee as a "turf war."

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Meanwhile, three suspects  are back in custody after they were released on bond that had been lowered.

Waco police Sgt. W. Patrick Swanton said Tuesday that Juan Garcia, Drew King and James Harris, all of Austin, were back in custody.

Garcia and King are charged with state-jail felony engaging in criminal enterprise, while Harris is charged with misdemeanor engaging in criminal enterprise. McLennan County Sheriff Parnell McNamara says Garcia and King had been released after a judge set their bonds at $50,000. Harris was freed after posting bond that was $20,000.

Their bonds were set before other suspects were arrested and had their bonds set at $1 million.

State District Judge Ralph Strother revoked the bonds for Garcia, King and Harris and arrest warrants were reissued.

On Monday, Dallas TV station WFAA reported that the Texas Department of Public Safety's Joint Information Center issued a bulletin May 1 that cautioned authorities about increasing violence between the Bandidos and the Cossacks. McNamara has said all nine people who were killed in the melee Sunday were part of those two groups.

The bulletin said the tension could stem from Cossacks refusing to pay Bandidos dues for operating in Texas and for wearing a patch on their vest that claimed Texas as their turf without the Bandidos' approval.

"Traditionally, the Bandidos have been the dominant motorcycle club in Texas, and no other club is allowed to wear the Texas bar without their consent," the bulletin said, according to WFAA.

The bulletin said the FBI had received information that Bandidos had discussed "going to war with Cossacks." It also outlined several recent incidents between the two groups, including one instance in March when about 10 Cossacks forced a Bandido to pull over along Interstate 35 near Waco and attacked him with "chains, batons and metal pipes before stealing his motorcycle," WFAA reported.

That same day, a group of Bandidos confronted a Cossack member fueling up at a truck stop in Palo Pinto County, west of Fort Worth, the bulletin said. When the Cossack member refused to remove the Texas patch from his vest, the Bandidos hit him in the head with a hammer and stole it.

The Bandidos "constitute a growing criminal threat to the U.S. law enforcement authorities," the Justice Department said in a report on outlaw motorcycle gangs. According to the report, the Bandidos are involved in transporting and distributing cocaine and marijuana and in the production and distribution of methamphetamine.

Five gangs from across Texas had gathered at Twin Peaks to, in part, settle differences over turf, Swanton has said.

Police and the restaurant operators were aware of Sunday's meeting in advance, and 18 Waco officers in addition to state troopers were outside the restaurant when the fight began, Swanton said. Police have acknowledged firing on armed bikers, but it was unclear how many of the dead were shot by gang members and how many were shot by officers.

Fox News' Casey Stegall and The Associated Press contributed to this report. 

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