It was a spasm of violence that stunned residents: some 200 black youths raising hell - what police called a full-blown riot - in Austin, Texas.

Angry black youths inexplicably converged by the Highland Mall, near an iconic haunted house attraction, and walked atop parked cars, fought among themselves, and hurled rocks at some 30 arriving police officers. Several people, including one officer, suffered minor injuries. Later, police said so many squad cars were need that the department was unable to provide adequate 911 emergency coverage to the rest of Austin. 

There were no reports of black-on-white violence, to be sure, as has often occurred at similarly gatherings across the country. The violence was unprecedented in hip and liberal Austin and, police later said, inexplicable.

From America's small towns to urban metropolises, black mob violence has been on the rise in recent years, despite President Barack Obama's pledge, as the first black president, to bring hope and change to a post-racial America. Some of the violence has involved rowdy black youths simply raising hell, coming together in threatening flash mobs or converging for events like Miami's Urban Beach Week; yet many gatherings of black mobs have involved vicious and unprovoked attacks on whites, such as one that recently occurred in Brooklyn, New York. Ten black youths blocked a white couple's car while shouting racial slurs, then beat up the husband and pulled the wife by hair onto the street.

Author and journalist Colin Flaherty has chronicled the trend of black mob violence in his book "White Girl Bleed a Lot: The Return of Racial Violence to America." Austin had escaped this trend until last Saturday night, when some 200 black youths rampaged near an iconic haunted-house attraction, the House of Torment, at the nearly empty Highland Mall. Video from an orbiting police helicopter revealed roving bands of youths walking around, with some occasionally engaging in fistfights among themselves. Some reportedly sported various gang colors.

In their reporting on the riot, Austin's media outlets followed a widely accepted rule of mainstream journalism today: they failed to mention that the rioters were black. Yet many Austin residents surmised as much -- and their suspicions were confirmed when mug shots were published of four of at least five black youths whom police arrested. A police commander subsequently told local website CultureMap Austin that, yes, the rioters were mostly blacks.
 
One gang banger was Charles Robertson-Davis, 22, whom police charged with inciting a riot. He was "constantly at the front of the crowd, challenging officers and encouraging other subjects in the crowd not to comply with police commands," stated an arrest affidavit.

Interestingly, Robertson-Davis is no stranger to Texas law enforcement. He used to be on the state's 10-most wanted list. He had a $10,000 reward on his head until he was captured in mid-April. According to the Texas Department of Public Safety, Robertson-Davis is a member of the Bloods, a violent black gang, and has a long rap sheet: assault, arson, resisting arrest, retaliation, assault of a public servant, possession of marijuana and controlled substances, tampering with and fabricating evidence, unauthorized use of motor vehicle, and failing to identify himself as a fugitive. Who was the judge who let him out of jail?

The Highland Mall is undergoing remodeling to serve as a branch of Austin Community College. But in its heyday, it was a popular and upscale shopping mall - until becoming a gathering spot for sometimes rowdy black youths, especially during a track meet called the Texas Relays, known informally as "Black Mardi Gras." Retailers dreaded the event as hundreds of black youths roamed about yet bought little merchandise. (For a YouTube clip of what's been happening, click here.) Over the years, shoppers increasingly stayed away. Major retailers pulled out as the Highland Mall contended with an "image problem." The mall was eventually sold.

Austin's police are clueless about why the riot occurred in hip and liberal Austin -- a college town, hi-tech Mecca, and the state's capital. Police Chief Art Acevedo and his commanders need to read Thomas Sowell's recent article in the National Review, "Early Skirmishes in a Race War." Sowell, an African-American and senior fellow with the Hoover Institution, related how blacks and whites have become dangerously polarized in recent years, with the most troubling example of this being the ominous trend of "unprovoked physical attacks on whites by young black gangs in shopping malls, on beaches, and in other public places all across the country today."

"Initial skirmishes in that race war have already begun, and have in fact been going on for some years," he wrote. "But public officials pretend that it is not happening, and the mainstream media seldom publish it at all, except in ways that conceal what is really taking place."

As officials grapple with Austin's first case of larger-scale mob violence by angry black youths, they're contending as well with the consequences of Austin's status as a sanctuary city: a school system overwhelmed with poor Hispanic children, many from chaotic and impoverished homes of illegal immigrant families from Mexico and Central America.

Austin's political and cultural landscape is dominated by rabidly liberal Democrats. As the city's social problems mount, it's unlikely that many in Austin's political class will get mugged by reality.