Seattle police say May Day marchers are welcome to protest Thursday, but officers are prepared to respond to assaults or property damage.

May Day has turned violent the past two years in the city. Last year police used flash bangs and pepper spray and arrested 18 people from a crowd that pelted them with rocks and bottles. Eight officers were injured.

On May Day 2012 masked marchers dressed in black broke windows and doors on downtown banks and stores and tried to set a fire at a federal building.

Socialist City Council member Kshama Sawant (CHAH'-mah SAH'-want) says she'll join a march for immigrant rights and a $15 minimum wage. She opposes violence saying it would "play into the hands of police and the political establishment."