HIALEAH — Assailants opened fire on a crowd outside a concert in Florida early on Sunday (May 30), killing two people and wounding more than 20, police and media reports said.

Three people got out of a white SUV and fired assault-style weapons and handguns at revellers gathered for an album launch party at the El Mula Banquet Hall near Hialeah, a city in Miami-Dade county, according to local media.

"I am at the scene of another targeted and cowardly act of gun violence," Miami-Dade police director Alfredo Ramirez wrote on Twitter. "These are cold-blooded murderers that shot indiscriminately into a crowd and we will seek justice."

The Miami Herald said 20 wounded victims were taken to local hospitals, and posted a photo of friends and relatives holding hands in prayer outside one trauma centre. CBS4 Miami said at least one victim remained in critical condition, and that police had no one in custody as of midday Sunday.

Ms Angelica Green, of Miramar, told reporters her son and nephew, both 24, were arriving at the event when they became among those shot and wounded. She said they were both now in stable condition at Miami's Jackson Memorial Hospital.

She told Local 10 News her son had telephoned her "frantic, saying he had been shot, that it hurts and that he loves us".

"He said the guys came with ski masks and hoodies, and just started shooting up the crowd," Ms Green said.

Florida Governor Ron DeSantis said state authorities were working to catch the perpetrators.

"Justice needs to be swift & severe!" he wrote on Twitter.

The United States saw at least 200 mass shootings in the first 132 days of this year, according to a report by the Gun Violence Archive, a non-profit research group. REUTERS