San Antonio: Police Chief William McManus told reporters that someone opened fire about 9pm during a performance at Ventura, a music venue and bar in the River Walk, just north of downtown.
McManus said police are searching for a suspect after someone began shooting during an altercation inside the bar. He said one victim, who was killed in the club, was a 21-year-old man. Another victim died on the way to a hospital, he said.
Five others were wounded and hospitalised Sunday night.
"It's nothing more complicated than an argument that occurred inside the club with at least one person pulling out a firearm," McManus said. "I'm told the individuals shot were patrons."
McManus said he could not confirm what the argument was about.
"We're working on that," he added. "I'm confident we will identify the individual and have that person in custody sooner (rather) than later."
The shooting took place just hours before an unrelated shooting outside a bar in Kansas City, Missouri, bar, which left two dead and 15 wounded. Police said that assailant, who was killed, opened fire on a line of people waiting outside the bar.
On Sunday morning, two police officers in Honolulu were fatally shot near the base of a volcanic crater. A fire was started and quickly spread, destroying five homes.
A neighbor told the Associated Press that a woman who had filed four days earlier to evict the alleged gunman left in an ambulance with stab wounds.
The officers who were killed were identified as Tiffany Enriquez, who was with the Honolulu police force for seven years, and Kaulike Kalama, who was on the force for nine years, Honolulu Police Chief Susan Ballard said at a news conference Sunday.
Police in Honolulu think the gunman, believed to be Jaroslav "Jerry" Hanel, died in the fire.