Fleeing a routine early morning traffic stop in downtown Austin, a suspected drunken driver crashed through a police barricade and sped down a street crowded with South by Southwest festival-goers, killing two and leaving a horrific trail of injured pedestrians over two blocks before hitting a taxi and a parked van.

Twenty-three people were taken to area hospitals. Two remain in critical condition with severe head injuries. Six others also remained hospitalized Thursday afternoon, including three in serious condition with injuries that include a spinal fracture, head injuries and other problems.

“The two critical patients I have a great deal of concern and worry about,” said Dr. Christopher Ziebell, emergency room director at University Medical Center Brackenridge. “Not everyone with these injuries survives.”

The driver — identified as Rashad Charjuan Owens, 21, of Killeen — was struck with a police taser and arrested as he tried to flee on foot. He was treated for minor injuries at University Medical Center Brackenridge and released into police custody, where he will face two charges of capital murder and 23 counts of aggravated assault with a vehicle.

“That vehicle was used as a weapon, and he will be charged with those crimes,” Austin Police Chief Art Acevedo said.

One of the dead, a Dutch musician and music agency employee identified as Steven Craenmehr, was riding a bicycle near the intersection of East 11th and Red River streets when struck. The other, an Austin woman on a moped, also was killed. Both were pronounced dead at the scene, officials said.

Another rider on the moped, a man, was injured.

The incident began around 12:30 a.m. Thursday when an Austin police officer tried to pull over a suspected drunken driver on the Interstate 35 frontage road. The driver pulled into a Shell gas station at East Ninth Street, using his turn signal and “feinting as if to yield” before speeding the wrong way down down Ninth Street, Acevedo said.

The suspect turned right onto Red River, crashing through a barricade and forcing a uniformed police officer to leap out of the way to avoid being struck, Acevedo said.

Red River, which was closed to vehicles, is home to many popular clubs that were hosting South by Southwest music showcases, and horrified music fans watched as the speeding four-door sedan slammed repeatedly into pedestrians, a bicyclist, moped and a taxi before jumping a sidewalk and striking a van in a parking lot, Acevedo said.

While the suspect was being chased down and arrested, witnesses sprang into action to help the wounded, shaking off the shock to help stanch the bleeding or merely hold hands in comfort, live music playing in the background.

Emergency crews, deployed throughout downtown for South by Southwest, arrived within minutes via motorcycle, bicycle and small off-road vehicles.

Frequent training in handling mass casualties paid off, said James Shamard, chief of staff for the Austin/Travis County Emergency Medical Services, as the first crews to arrive began to triage patients. Cards marked with red were placed with five of the most critically injured, who were taken to nearby University Medical Center Brackenridge within 15 minutes, Shamard said.

Five victims with lesser injuries were given cards marked in yellow and taken to St. David’s Hospital and South Austin Medical Center within 21 minutes, Shamard said. Thirteen tagged with green cards, indicating non-life-threatening injuries, were taken to other hospitals within 50 minutes, he said.

Black-marked tags were placed on the man and woman who were pronounced dead at the scene, Shamard said.

Most of the pedestrians hit were between Ninth and 10th streets, said Acevedo, who urged anybody who witnessed the crashes to call Austin police at 512-974-5186.

Police will reassess procedures used to block off streets during special events, as is common after a tragedy, Acevedo said, “but when somebody acts intentionally, it’s very difficult to stop.”

A person “willing to drive down a street, mowing people down, will crash through or go around a barricade,” he said. “This is an individual that showed no regard for the human beings he plowed through … to get away.”

Sturdier barricades can pose other problems for emergency crews and vehicles that need access to widespread events such as South by Southwest, he said.

The suspect, Owens, was booked into Travis County Jail at 5:44 a.m. No bail was set.

Police obtained a search warrant for blood samples to assess Owens’ blood-alcohol level and are awaiting results, Acevedo said.

Acevedo said he urged South by Southwest managers to continue with planned events. “We cannot allow one individual, through his selfish acts … to ruin a wonderful event, a worldwide event,” he said.

Roland Swenson, managing director of SXSW, said staff are contacting all venues to determine if events will change. Several cancellations have been announced.

“As much as we’d like to go home and spend time absorbing the shock of this horrific event, we feel our best use is to continue to operate today,” Swenson said. “We will announce changes to the schedule as they occur today.”

In the hectic moments after the series of crashes early Thursday, witnesses described a chaotic scene.

Scott Jakota, a musician from Indiana in town to play SXSW, said he was one of the first people hit. He said the driver “gunned” the car, “and I was thrown up in the sky.” He appeared to have a leg injury and was being helped by his friends.

Ally Hulton, a 28-year-old from Los Angeles, was smoking a cigarette on the balcony of her friend’s apartment on Red River when she saw a car drive down the street “at full speed” before hitting someone.

It then appeared to accelerate into a crowd of people, she said.

“About 10 bodies went flying,” Hulton said.

An American-Statesman photographer on the balcony of the Mohawk nightclub at the time of the incident said he saw some bystanders attempting to provide first aid to victims while others sat stunned on curbs with their hands over their mouths. He said the band playing at the time, X, finished its set, unaware of what had happened.

Transmission Events, which owns the Mohawk, said on Twitter: “Our thoughts and prayers are with the families of the victims and injured from tonight’s tragedy. Please check and make sure everyone you know is home safe tonight.”

With additional reporting by Philip Jankowski, Peter Blackstock, Nancy Flores, Ben Wermund and Jay Janner.