A man arrested over a mass shooting that left six people dead had posted a live Facebook video of himself posing with a handgun just hours before the incident, police have said.
Smiley Martin, 27, was found at the scene with gunshot wounds, and taken to hospital where he was “quickly identified as a person of interest”, Sacramento police said in a statement.
He was arrested in hospital on Tuesday over his alleged involvement.
Mr Martin is the brother of Dandrae Martin, 26, the first suspect arrested following the shooting in the city centre in the early hours of Sunday.
The older brother will be transferred to jail on charges of having a firearm while banned and possessing a machine gun as soon as his condition improves, police said.
Police did not explain the men’s alleged roles in the shooting, or whether further suspects are still at large.
But the force’s chief, Kathy Lester, has said “multiple” shooters were involved in the incident, which investigators believe was sparked by a row at a nearby nightclub.
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More than 100 shots were fired and, along with the shell casings, detectives found a stolen handgun that had been turned into a weapon capable of automatic gunfire.
Police said the injured were “suffering from gunshot wounds ranging from minor to critical but stable”.
Just moments before violence erupted, several people could be seen in videos fighting on a street lined with an upscale hotel, nightclubs and bars when gunshots sent people scattering.
While hundreds fled to safety, six people were killed and 11 injured, including Smiley Martin.
Four of the 11 injured are in critical condition, the Sacramento Fire Department has said.
A day later, police arrested Dandrae Martin as a “related suspect” on charges of assault with a deadly weapon and being a convict carrying a loaded gun.
He appeared in court on Tuesday.
Sacramento’s County Coroner identified the women killed as Johntaya Alexander, 21, Melinda Davis, aged 57 and 21-year-old Yamile Martinez-Andrade.
The three men were Sergio Harris, 38, Joshua Hoye-Lucchesi, aged 32; and 29-year-old De’Vazia Turner.
Mr Turner’s mother, Penelope Scott, said her son “was walking down the street and somebody started shooting and he got shot. Why is that happening?, adding: “I feel like I’ve got a hole in my heart.”