Rival biker gangs clashed violently in Waco, Texas, on Sunday afternoon, in a brawl that ultimately left nine gang members dead and at least 18 others injured. As the fight spilled out of a local restaurant and into the parking lot, participants reportedly used fists, chains, knives and later firearms to attack one another. Eventually they exchanged gunfire with police. Waco law enforcement announced Monday that 170 people had been arrested and will be charged with engaging in organized crime. The brutality terrorized the surrounding community, leading to large-scale evacuations, closed businesses and ongoing fears, though remarkably no physical harm to bystanders. The incident has temporarily shoved biker gangs and their overwhelmingly white membership into the national spotlight. But these groups -- which the FBI labels outlaw motorcycle gangs, or OMGs -- typically receive far less media attention than urban street gangs, though the biker gangs' criminal networks reach across the country and have erupted violently before. Sunday's bloodshed reportedly began inside the bathroom of a local Twin Peaks "breastaurant" that has catered to bikers in the past. Between 150 and 200 gang members were apparently inside at the time, and one witness said that as many as 30 gang members were shooting at each other at the height of the battle. Police have accused the Waco restaurant of being uncooperative in earlier attempts to scale back large and often contentious biker gatherings, and now its clientele has led to serious consequences for management. On Monday, the Twin Peaks corporate office revoked the establishment's franchise, stating that "the management team of the franchised restaurant in Waco chose to ignore the warnings and advice from both the police and our company, and did not uphold the high security standards we have in place to ensure everyone is safe at our restaurants." The Texas Alcoholic Beverage Commission had already closed the restaurant for a week in order to avoid further possible violence. Nearby businesses that fell within the police perimeter were also put on lockdown or evacuated following the initial melee. Walmart reportedly closed early Sunday after being cleared. Best Buy, Cabela's and other stores in the Central Texas Marketplace -- the shopping center that contains the Twin Peaks restaurant -- remained closed Monday as the investigation continued. The manager of a local Denny's told the Austin American-Statesman that a "huge" group of bikers came into her restaurant a few hours after the shooting. Many were served but left abruptly a short time later, some without paying their checks. The manager said a SWAT team showed up minutes after the bikers departed, leaving her and other patrons rattled. The Waco Tribune reported that "other local dining and drinking establishments" closed early Sunday amid fears that gang members might be looking to resume the violence. Law enforcement officials in Texas said they've received numerous retaliatory threats from biker gangs following Sunday's incident and have gone on high alert in case of any backlash. Biker gang violence is not unusual in Central Texas. OMGs play a key role in methamphetamine and marijuana trafficking throughout the region. The FBI says they're involved in cross-border drug smuggling as well as domestic drug trafficking, prostitution, human trafficking and other criminal enterprises. Police said that five OMGs took part in the violence on Sunday, though authorities haven't identified the organizations by name. According to a 2013 report by the FBI's National Gang Intelligence Center, there are more than 300 OMGs active in the U.S. Another study suggests that the vast majority of their members are white, though some groups have embraced multiracial membership -- and some of the suspects arrested Sunday were not white. Though the OMGs constitute only 2.5 percent of all gang members across the nation, the FBI says these groups "pose a serious national domestic threat." An FBI survey of law enforcement officials also suggested that the threat from OMGs was "higher than their membership numbers would indicate." According to the survey, 14 percent of respondents identified OMGs "first amongst their most problematic gangs within their respective jurisdiction." The report cited the groups' "solid organizational structure, criminal sophistication, and their tendency to employ violence to protect their interests" as primary reasons for concern. So here we have established criminal networks with a history of well-armed brutality endangering their neighborhoods. Surely all Americans should be concerned about the role these mainly white gangs play in the disintegration of the nation's white communities and the scourge of white-on-white crime. Surely all of this will be discussed on cable news panels and talk radio over the coming days. Surely.