Updated at 7.15pm
Twenty-five people have been shot at a downtown nightclub in Little Rock, Arkansas.
The shooting at Power Ultra Lounge arose from a dispute among club-goers and not from an active gunman or a terror-related incident, said police.
Officers said 25 people were shot and three others suffered unrelated injuries but all are expected to survive.
A video posted online showed several bursts of gunfire - more than 24 shots in 11 seconds - about half a minute into a break in the raucous concert in the packed house for Finese 2Tymes, a performer from Memphis.
Club patron Darryl Rankin said he was recording the show on Facebook Live when gunfire erupted and that one of his friends is now at a hospital with a bullet "stuck in his spine."
Police cordoned off the block as crime-scene technicians gathered evidence from inside and outside the club. Glass from the club's second story windows littered the ground, along with empty drink cups.
Police chief Kenton Buckner said "some sort of dispute broke out between people inside" and there are "probably multiple shooting suspects."
The shooting follows a week in which there have been about a dozen drive-by shootings in Little Rock, though there is no indication the events are linked.
Little Rock mayor Mark Stodola said: "My heart is broken this morning - my prayers are with the victims of this tragedy. "
"We are committed to doing everything possible to bring safety to our city. We need everyone to help."
"Little Rock's crime problem appears to be intensifying," said Govenor Asa Hutchinson.
"Every few days it seems a high profile shooting dominates the news, culminating with this morning's event. I have spoken this morning with Mayor Stodola and I have offered both my heartfelt concern over this senseless violent tragedy and state assets as needed to address the continued threat of violence in our community."
Raida Bunche waited outside the club after she had heard from a friend that her son had been at the club. Later, she said she discovered her son ran out once the shooting began and was unharmed.
"I'm sick of all the killing and I'm tired of all the shooting, the kids getting hurt," said Ms Bunche.
The club's Facebook page promoted Friday night's show with a poster depicting a man pointing what appears to be a gun at the camera. A call to a number listed for Finese 2Tymes' booking agent wasn't immediately returned Saturday.
One person was killed and six people were hurt in a mass shooting in May at a downtown concert in Jonesboro, Arkansas, about 115 miles north-east of Little Rock. In that case, two men were charged with first-degree murder and six counts of first-degree battery.
Power Ultra Lounge's alcohol license was suspended by Arkansas Alcohol Beverage Control officials who set a hearing for July 10.
Potential violations include allowing possession of weapons on the premises, disorderly conduct and failure to be a good neighbour, said the alcohol agency.