Gunfire erupted inside a packed nightclub in Cincinnati, Ohio, early Sunday morning, killing at least one person and injuring 14, and police said they were still looking for the shooter.
The motive was unclear, but Cincinnati Assistant Police Chief Paul Neudigate said on Twitter that "there are no indications this incident is terrorism related."
The shooting took place around 1 a.m. when hundreds of people were inside the Cameo Nightlife club, which the Cincinnati Police Department said has had "multiple problems" in the past.
"At this point it's unclear exactly what instigated the shooting," Captain Kimberly Williams said at a televised briefing. "Just a lot of chaos when the shots went off."
The shooting comes less than a year after a gunman opened fire at a gay nightclub in Orlando, Florida, killing 49 people. It was the deadliest mass shooting in U.S. history.
Police initially said they believed at least two shooters were involved in Cincinnati, but later Neudigate said in a Twitter message that there was only one reported gunman, though police were still trying to determine if there were others.
Hours after the shooting, the suspect was still at large, and police did not have a good description, in part because witnesses were reluctant to cooperate, Williams told WCPO.
"We are in the middle of a very horrific situation that occurred at the nightclub with multiple victims," Neudigate told NBC News.
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"It's going to be a long night for our homicide units to investigate this incident, but right now things are stable."
Several of the victims in Cincinnati had life-threatening injuries, WLWT-TV reported on its website, quoting Neudigate, who said hundreds of people were in the nightclub at the time of shooting.
The University of Cincinnati Medical Center admitted eight people injured in the shooting, one of them in critical condition, a spokeswoman told NBC News. A representative of the hospital could not be reached immediately for comment.
Cameo Nightlife's Facebook page says it features "College Friday's" for students 18 and older and "Saturday's 21+ grown and sexy night."
The club, a large single-story structure, is a 7-mile (11 km) drive from downtown Cincinnati near the southeast corner of the city, the heart of the second largest metropolitan area in Ohio with more than 2 million residents.
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