http://www.nbcnews.com/news/us-news/may-day-protests-turn-violent-portland-police-cancel-permits-n753611
South of Seattle, in Olympia, the state capital, police said Monday night that protesters were targeting officers and journalists with rocks, bottles and pepper spray. Some were using slingshots to propel rocks, police said.
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Rallies began at noon (3 p.m. ET) in Portland. Police reported that members of an anarchist group began throwing rocks, lead balls, full cans of soda, glass bottles and "incendiary devices" late in the afternoon.