Police responded to reports of multiple people shot at around 3 a.m. at a sports bar on Hillcroft Avenue, Assistant Chief James Skelton told reporters, NBC News reported.
The shooting happened at an after-hours club, which Skelton said is an issue that police are trying to address in Houston.
Three people who were shot were taken to hospitals by the Houston Fire Department, and three others were taken to hospitals in private vehicles, he said.
The four patients in critical condition were undergoing surgery Sunday morning, he said.
“We do have some video, which is good,” Skelton said. Police were looking for a black Toyota Camry or Corolla with two people inside.
“We know this is more of an isolated attack,” he said. All the victims were male, he said, and the shots appear to have come from outside the bar.
Skelton said after-hours nightclubs draw crime like DUIs and assaults, and that police are working to shut them down in the city.