At the end of April and the beginning of May, explicit instructions began flying across Weibo: Meet in front of Kunming's main department store at 1:30 on May 4 to "go for a walk" a popular euphemism in China for protesting.

WSJ: Behind Chinese Protests, Growing Dismay at Pollution

Such land disputes account for 65% of "mass incidents" the government's euphemism for large protests in rural areas, according to Yu Jianrong, a professor and expert on rural issues at the state-run Chinese Academy of Social Sciences.

WSJ: Chinese Village, Police in Standoff Over Villager's Death