KORONADAL CITY -- Four persons, including a minor, were arrested today by police authorities here during anti-illegal drug operation as the PNP intensifies implementation of Oplan Double Barrel Alpha. Supt. Barney Condes, Koronadal City police office, in a report, identified the suspects as Mary Jell Millan, 20, Rafael Millan, 21, both of Barangay GPS, this city, Eric Bustamante, 22 of Barangay Zone 4 and a minor.