There had already been rioting and attacks on and massacres of Jews in 1921 and 1929. During the 1930s Palestinian Arab popular discontent with Jewish immigration and increasing Arab landlessness grew. In the late 1920s and early 1930s several factions of Palestinian society, especially from the younger generation, became impatient with the internecine divisions and ineffectiveness of the Palestinian elite and engaged in grass-roots anti-British and anti-Zionist activism organized by groups such as the Young Men's Muslim Association. There was also support for the growth in influence of the radical nationalist Independence Party ("Hizb al-Istiqlal"), which called for a boycott of the British in the manner of the Indian Congress Party. Some even took to the hills to fight the British and the Zionists. Most of these initiatives were contained and defeated by notables in the pay of the Mandatory Administration, particularly the "mufti" and his cousin Jamal al-Husayni. The younger generation also formed the backbone of the organisation of the six-month general strike of 1936, which marked the start of the great Palestinian Revolt. According to Khalidi this was a grass-roots uprising, which was eventually adopted by the old Palestinian leadership, whose 'inept leadership helped to doom these movements as well'.