Several people have been arrested after a May Day protest in downtown Seattle turned violent Tuesday night.
Q13 Fox reports police were using pepper spray and "ball blasts," which give off a bang and a dose of pepper, to control the crowd.
The protest turned violent around 7:45 p.m., with protesters throwing rocks, bottles, metal bars at officers. Police officers ordered the protesters to clear the area or face arrest.
Reuters reports that one protester was seen using a skateboard to smash windows at a Walgreens drug store in the city's Capitol Hill neighborhood, and others overturned trash cans and lined up newspaper display racks to block police.
Seattle police tell Reuters that as of 9 p.m. local time, 11 adults and 2 juveniles had been arrested for assaults and property damage. Several people were shown on local TV stations being taken into custody.
Seattle police said in a tweet that one officer was injured by a thrown object. His condition was not immediately clear.
The violence broke out as darkness fell in Seattle following a day of May Day rallies in cities across the U.S. that were planned by a coalition of organized labor activists, students and civil rights advocates to call for an overhaul of immigration laws.
This is the second year in a row a Seattle May Day protest has turned violent, according to Q13 Fox.
Reuters contributed to this report.