A gunman killed a woman and seriously wounded three others early on Sunday when he shot into a crowd as people streamed out of nightclubs in Texas, police said.
The Austin Police Department said it was seeking Endicott McCray, a slender 24-year-old black man.
The incident began shortly after 2:15am (0715 GMT) in the busy downtown area of Austin filled with bars and nightclubs, with police warning people on Twitter to steer clear of the area due to an "active shooter".
Active shooter incident downtown, multiple victims. Stay away from downtown. Media: Dont call for updates at this time, more to follow. PIO6
— Austin Police Dept (@Austin_Police) July 31, 2016
One woman was killed and three other women were rushed to a local hospital with gunshot wounds, the Austin-Travis County Emergency Medical Services said.
A fifth victim, a man, refused aid, the ATCEMS said.
Police later confirmed there had been a second, separate shooting incident in the area, which took place just minutes later, although only the gunman was injured.
At the time, police initially thought they were facing multiple shooters. Instead, it turned out to be one individual armed with a rifle who was firing from different spots.
— Sam Vedamanikam (@RalphGreNader) July 31, 2016
'Very chaotic scene'
At a pre-dawn press conference broadcast via Periscope, Austin Police Chief of Staff Brian Manley said the shooter in the first incident, was still at large.
After receiving reports of the first incident, officers arrived in the busy downtown area where they found "a very chaotic scene," Manley said.
There appeared to have been a disturbance during which an individual pulled out a gun and fired into a crowd of pedestrians, he said.
A woman in her 20s was shot and died at the scene.
Seven minutes later police were notified of a second shooting inside a nearby parking garage, he said.
In that incident, an individual pulled out a gun and fired, but was then confronted by witnesses who knocked him down and disarmed him.
Manley said the alleged shooter, who was injured, was apprehended and taken to hospital. His condition was not immediately clear.
It was unclear if the shooters knew any of their victims, with Manley saying it was part of the ongoing investigation.
Sam Vedamanikam, 26, told the Austin American-Statesman newspaper that he and several friends were leaving a dance club and heading to their car when they heard four or five gunshots.
"There were just tons of people on Sixth Street and I see all of them jump toward the ground," Vedamanikam told the newspaper. "A lot of people were screaming."
The incident comes a day after a gunman attacked a suburban Seattle home killing three people.
On July 25, a shooting at a nightclub for teenagers in Fort Myers, Florida left at least two people dead and 14 injured.