SAN BRUNO, Calif. (AP) — Police have arrested one of two teenagers they say opened fire at a San Francisco Bay Area shopping mall, 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 described as acting in concert with the shooter also was arrested.

Police are searching for the other shooting suspect, identified as 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.