SA Police say 12 men and one boy have been arrested over "a series of skirmishes and confrontations" in Adelaide's CBD early on Monday morning, but none of them has been charged with the murder of a man found on North Terrace.
The 25-year-old man died shortly after he was found near the corner of West Terrace about 2am.
He had multiple stab wounds to his chest, and police have said he was from Victoria.
Assistant Commissioner John Venditto said eight people had been arrested over weapons offences, two were arrested over an aggravated assault at the Nairobi Affair Lounge in March, one over an aggravated assault in Salisbury last month and another had outstanding bench warrants.
Another man was arrested for breach of bail.
Assistant Commissioner Venditto said two groups appear to have been involved in "a series of skirmishes and confrontations" between themselves, but that did not mean there was no threat to the public.
"They've got bladed weapons, they've got other weapons, and the threat is also there to the frontline police who respond quickly and not always in numbers and sometimes we might be outnumbered so the threat to the public is there."
Arrests across Adelaide's CBD
Assistant Commissioner Venditto said the night of violence began when a "reasonable size group" of people was seen running out of Sia Furler Lane, near Hindley Street, before the man was stabbed at the corner of North Terrace and George Street.
"The circumstances of that murder are the attackers ran down the victim and then, when he fell, he was stabbed on the ground and assaulted," he said.
He said there may have been more confrontations that police were not aware of.
"Some of them we're aware of and others we're not and we're asking for public assistance, if anyone saw it or filmed [it], and realise it now may be helpful to us," he said.
Seven men were then arrested near the Quest on Franklin hotel and, later, another five — including a 16-year-old boy — were arrested in Pulteney Street.
A car was seized after police allegedly found two knives, a machete and cash inside.
The last man was arrested in Pirie Street.
Nine of the arrested individuals are from Adelaide's north, one is from the western suburbs, one from the Melbourne suburb of Werribee and two others have no fixed address.
They are expected to appear in the Adelaide Magistrates Court on Tuesday.
Police are also investigating whether a possible robbery in King William Street was connected with the same men.
Detectives have also been at the Mantra hotel on Hindmarsh Square and the Rockford hotel on Hindley Street.
Arrested men connected with gang taskforce
SA Police launched a special taskforce called Operation Meld last year, targeting gangs made up largely of young men from Adelaide's Sudanese community.
In February, they said violence had begun spilling out into Adelaide's wider community, including through a series of robberies.
Assistant Commissioner Venditto said Monday's violence was connected with the same group of people.
"They're certainly part of the gangs that Operation Meld has been focused on," he said.
"It's unfortunate it has come to this, because whilst there's been incidences, they've been … fewer — and then it's erupted to this last night," he said.
