One person was killed and 14 injured in a shooting at a crowded hip-hop nightclub about 1 a.m. Sunday in Cincinnati.
Assistant police chief Paul Neudigate described the crime scene as "chaotic". Although the local police chief first said there were several gunmen involved, a top official later took to Twitter to say that so far there was only one reported gunman.
Police said they would give an update after 2:00am AEDT.
A single body was removed by the coroner shortly after 6 a.m.
Numerous victims taken to area hospitals have life-threatening injuries.
"At this point it's unclear exactly what instigated the shooting", Capt Williams told reporters.
It is not yet known how severely injured the other victims are. She said earlier in the evening there was a large crowd inside, but that "by the time shots were fired, individuals ran outside, so there's not a lot of people inside the club". He had reportedly said that he had shot two Iranians after shooting the Indians.
Cincinnati police believe that "at least a couple of shooters" were involved, Williams said. In fact, the club is also known to hire police for extra security, with two officers at the entrance and two in the auto park always present. Several others were taken to the other five hospitals in the vicinity, including Mercy Health Anderson Hospital, Bethesda North Hospital, Mercy West Hospital and Christ Hospital.
The shooter, Omar Mateen, pledged allegiance to the Islamic State jihadist group in a 911 call to police during the assault on the Pulse nightclub.
"We are the region's Level One trauma center, so we prepare and train for situations like this and hope they never happen", Martin said. Saturday nights are 21 and above and promoted as "grown and sexy" night.