In February 1988, the government hiked food prices by 40%. On April 21, a new wave of strikes hit the country. On May 2, workers at the Gdańsk Shipyard went on strike. That strike was broken by the government between May 5 and 10, but only temporarily: on August 15, a new strike took place at the "July Manifesto" mine in Jastrzębie Zdrój. By August 20 the strike had spread to many other mines, and on August 22 the Gdańsk Shipyard joined the strike. Poland's communist government then decided to negotiate.