Cops were called to the Kansas City bar where four people were gunned down hours before shots rang out — but left when the troublemaker couldn’t be found, city officials said Tuesday.

That’s when he returned with a second gunman and opened fire.

Kansas City, Kansas, Police Chief Michael York said a dispute in the bar set off the tragic events.

“The dispute resulted in the suspect being ejected from the establishment,” York said at a press conference about the shooting Sunday morning at Tequila KC.

“A few hours later the suspects returned to the bar armed with handguns and appeared that they fired at specific individuals,” he said. “As they left the scene they continued to fire into the crowd.”

Police have arrested one of the shooters, Javier Alatorre, 23, who was found in a house in nearby Kansas City, Missouri, police said. The second suspect, Hugo Villanueva-Morales, 29, is on the loose.

Both men have been charged with first-degree murder.

York said Villanueva-Morales should be considered armed and dangerous.

Jose Valdez, a bartender at Tequila KC, told Fox4 News that he got into a beef with one of the gunmen earlier in the night and kicked him out of the bar.

“We never, we never service him,” Valdez said. “We try to keep people like that out of the bar. Right then and there he picked up a cup that was right there and threw it at me.”

Valdez said the man was kicked out.

“When he came in the second time he did not say nothing,” the bartender said. “He walked in and looked for who he was looking for and just started shooting.”

Police did not provide details of the dispute in the bar, saying the shooting remains part of an active investigation.

York also identified the four shooting victims as Alfredo Calderon, 29, Everado Meza Aguirre, 29, Francisco Anaya Garcia, 34, and Martin Rodriguez Gonzalez, 58.