More than 30,000 workers walked off their jobs in May 1919 in what came to be known as the Winnipeg general strike. The strike was a product of postwar recession, labour conditions, the activity of union organizers and a large influx of returning World War I soldiers seeking work. After many arrests, deportations, and incidents of violence, the strike ended on 21 June 1919 when the Riot Act was read and a group of Royal Canadian Mounted Police officers charged a group of strikers. Two strikers were killed and at least thirty others were injured on the day that became known as "Bloody Saturday"; the event polarized the population. One of the leaders of the strike, J. S. Woodsworth, went on to found Canada's first major socialist party, the Co-operative Commonwealth Federation, which later became the New Democratic Party.