Philadelphia Police enforced the city's curfew law on minors Saturday night



On Friday, Mayor Michael Nutter announced stepped-up police presence around the city in an effort to combat flash mobs of teenagers that have led to assaults and robberies around the city.



Police said they handed out seven curfew fines on South Street on Saturday evening.



On Friday evening, eight juveniles received curfew fines.



By city law, children under the age of 13 must be inside by 10 p.m. Teens between the ages of 13 and 18 must be at home by midnight. There are penalties for minors and parents who break the curfew.