A series of shootings across the country Sunday killed six people, including two police officers in Hawaii.
In Kansas City, Missouri, police said that at least two people were killed and that 15 more were injured in a shooting outside a bar.
Officers found "a chaotic scene" at 9ine Ultra Lounge shortly before midnight Sunday and had to call in help from around the city. Two people were found dead: a woman in the parking lot and a man whom police believe to be the gunman.
Police identified the alleged shooter Monday as Jahron Swift, 29. The woman was identified as Raven Parks, 25.
A security guard shot the gunman, who opened fire on a line of people waiting to enter the bar, police said. His motive was not known.
At least 15 people were being treated at area hospitals. Three were listed in critical condition.
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In a tweet, Kansas City Mayor Quinton Lucas praised the security guard, who he said "appears to have kept the situation from being even worse."
Police Chief Rick Smith described the incident as part of the city's "culture of violence."
"We have to change the trend that it's OK to engage in this kind of behavior and that it's OK to not say when someone does something wrong," Smith said. "That's not OK."
A Facebook post showed that the club hosted a sold-out celebration party Sunday night as the Kansas City Chiefs clinched a spot in the Super Bowl next month.
"It's hard to stand here and talk about this kind of tragedy on really one of the best days Kansas City has had in a long time," Jackson County Prosecutor Jean Peters Baker said.
In Honolulu, police officers Tiffany Enriquez and Kaulike Kalama were killed as they responded to a stabbing call Sunday.
Police Chief Susan Ballard said a man shot at the officers as they attended to a woman who had been stabbed in the leg. Police said the home caught fire and became fully engulfed in flames. The fire then spread to six other homes.
The suspect, whom police identified as Jerry Hanel, who is in his 60s, and two women believed to have been inside the house remained unaccounted for. Officers were scouring the area for remains.
Ballard said Hanel did not have any gun permits. Court documents show that Hanel has a history of erratic behavior, including making false 911 reports, NBC affiliate KHNL reported.
His attorney told the station that Hanel had delusions that he was being tracked by the FBI.
Honolulu Mayor Kirk Caldwell tweeted his condolences to the families of the two officers, calling their deaths an "unprecedented tragedy for not only the city and county of Honolulu but the entire state of Hawaii."
In San Antonio, two people were killed and five others were injured in connection with an argument inside a club Sunday night, police said.
The argument broke out during a concert, resulting in the gunman's pulling out a weapon and firing at people inside.
One person died at the scene and six others were taken to a hospital, where one was pronounced dead. All were patrons of the bar.
Police announced the arrest of a 19-year-old suspect in the shooting Monday, identifying him as Kieran Christopher Williams. Williams is facing capital murder charges, though police said on Twitter that he could also face additional charges.