MIAMI (Reuters) - Police in Miami have started enforcing a curfew for children under the age of 17 in the hope of cutting down on the number of youngsters out late during the approaching spring school break.

The Juvenile Curfew Ordinance, in place in Miami-Dade County for nearly two decades, makes it illegal for youngsters to be on the streets without adult supervision from 11:00 p.m. Sunday to 6:00 p.m. Thursday. The weekend curfew is from 12:00 a.m. to 6:00 a.m., according to the Miami Police Department.

The ordinance lets police decide when to step up enforcement.

The curfew has some exceptions, including traveling for work or school, running an errand with written permission from a parent and being on property where a youngster lives or at a neighbor's house.

(Reporting by Kevin Gray)