Nearly six months to the day of his arrest, 23-year-old Javier Campos is being arraigned in San Francisco for the June 9 shooting at 24th and Treat streets that injured nine people.

Campos, who was arrested a week after the shooting in Santa Cruz, is now charged with one count of discharging a firearm from a motor vehicle and causing great bodily injury, eight counts of assault with a semi-automatic firearm and causing great bodily injury, and three counts of unlawful firearm possession. Prosecutors also say that the shooting occurred "for the benefit of a criminal street gang," and Campos is further charged with committing these crimes while out on bail in another case.

It's not clear why it took six months for the DA's office to file charges in the shooting, but DA Brooke Jenkins announced the charges on Friday, with Campos scheduled to be arraigned at 1:30 p.m.

"The Mission District shooting was horrifying and once again demonstrates the horrors of gun violence," said Jenkins in a statement. "My office will continue to prosecute these types of acts to the fullest extent. Brazen shootings like this one exact a heavy toll on our neighborhoods and communities."

Campos is accused of spraying a crowd of people with bullets who had gathered for a sixth anniversary celebration of Dying Breed, a skate shop. The shooting was a drive-by, and initial evidence suggested there were two gunmen involved.

As Mission Local reports, Campos went on to appear to brag about the shooting in an Instagram story, posting the message, "Ima make sure them n**** neva post up on that block again."

Shortly after his arrest, SFist learned that Campos was also wanted by Oakland police in connection with the January 23 shooting of 18-year-old Mario Navarro. That shooting also involved shots fired from a car a large gathering of people — in that case, a group gathered in a gas station parking lot for a music video shoot.

Per Mission Local, Campos also had other outstanding warrants from around the Bay. Despite living in Richmond, Campos reportedly spent much of his time in SF's Mission District, where he lost both his father and stepbrother to gun violence when he was 12 years old.

Prosecutors intend to ask the court that Campos be held without bail pending trial.

Previously: Alleged Gang Member Arrested For Mission Shooting Was Wanted for Oakland Music Video Shooting That Killed One