SAN BRUNO (AP) — Police have arrested one of two teenagers they say opened fire at a San Francisco Bay Area shopping mall days earlier, wounding two people.

San Bruno Police Chief Ed Barberini announced the arrest Saturday of a 16-year-old San Francisco boy on suspicion of attempted murder. A 15-year-old boy suspected of being an accomplice also was arrested.

Police are searching for the other suspect in the shooting, 18-year-old Deandre Gantt of San Francisco.

Police say two groups got into an argument last Tuesday at The Shops at Tanforan. One person in each group pulled a gun and opened fire. Panicked customers and employees fled or hid.

Barberini won’t say what sparked the confrontation but calls the argument relatively minor.

Two teenagers who were wounded are expected to recover.