AUSTIN, Texas (KXAN) — A second suspect has been arrested in connection with the mass shooting that killed one and injured 13 others in downtown Austin’s Sixth Street over the weekend.

The suspect is a 17-year-old who will be charged with aggravated assault, a city source confirmed to KXAN. Killeen ISD police say the suspect was arrested at Harker Heights High School Monday.

On Saturday afternoon, the Austin Police Department (APD) confirmed the arrest of another juvenile in connection with the deadly shooting.

Douglas John Kantor, 25, died from his injuries at an Austin hospital Sunday at 12:01 p.m. after the shooting, police say.

At an initial police briefing, APD Police Chief Joseph Chacon said 11 people were receiving treatment at one hospital, while one victim went to a separate hospital, another received treatment at an emergency room and another self-transported.

Chacon said his officers rushed six patients to the hospital in their patrol vehicles, while Austin-Travis County EMS paramedics ended up taking four. Three were transported in personal vehicles, police said.

Police explained officers took some victims in patrol cars because the size of the large crowd on Sixth Street and the chaotic scene made it difficult for EMS and the Austin Fire Department to get to the area. Chacon credited his officers, who were working in five shifts, for applying first aid and tourniquets to save some of the victims.