SEATTLE — Police used flash bangs and pepper spray against some protesters pelting them with objects late Wednesday, as a spurt of violence erupted after a May Day march for immigration reform ended. Several dozen protesters, many using bandanas to cover their faces, began clashing with police in downtown Seattle hours after a peaceful march ended. Protesters threw several objects, possibly rocks and other items, at police officers and news crews. As they moved through streets, they flung street barriers and trash cans on the streets and banged on vehicles with people inside. Officers responded by using flash bangs and pepper spray. Officers also used their bikes as shields in an attempt to control the crowd and protect businesses from being vandalized. A few people were seen taken into custody. Many of the protesters are self-described anarchists. A local anarchist website said protesters would attempt to disrupt the day. The violence is reminiscent of last year’s May Day when anarchists broke windows of store fronts and vehicles and used smoke bombs. Protesters also targeted a federal building, throwing a smoke bomb inside. The violence marred a May Day that immigrant activists hoped would put a focus on immigration reform. Thousands of people marched about 2 1/2 miles from the Central District toward Seattle’s downtown Jackson Federal Building after a May Day rally supporting immigrant rights and labor. Many carried signs, with messages such as “We are America,” and “There are no illegal humans.” One sign suggested forgetting about marijuana and instead asking the United States to “Legalize my mom,” a reference to Washington’s recent legalization of marijuana. Other demonstrations and rallies in Olympia, Mount Vernon, Spokane, Vancouver, Walla Walla, Wenatchee and Yakima went along peacefully.