Drone In Highland Park Flying Over Dog Park

Hello, This morning, someone was flying a drone over the new OLEA (Dog Park). It felt very odd to have it buzzing over head, but I was not sure what to say to the person who was doing so. I called 311 and was told that drones are not allowed over city parks without a registration. I was also told to call 911 to have a police officer come by. By the time the officer came by, the person was gone. Please, if you see a drone flying over the park, call 911. Thank you, Jill Weiss