Rochester police are reporting 15 arrests in the hours after the Puerto Rican Festival.
Police say there were disorderly crowds and large car caravans on the city's north side -- but there were no major incidents.
Several objects were set on fire in the street and bottles were thrown at officers. Police used warnings, pepperballs and the Long Range Acoustical Device to disperse the crowds. Also, a New York State Police Helicopter was used for observation.
Eleven arrests were traffic related, three were for disorderly conduct and one was for resisting arrest.