In the mid-1950s, the  Revolutionary Government of the Republic of Indonesia rebellion broke out. In November 1957, senior Masyumi figures Mohammad Natsir, Sjafruddin Prawiranegara and Burhanuddin Harahap, joined the rebels in the Sumatran city of Padang. The Masyumi Party refused to condemn their actions, which damaged the party's image. In 1960, President Sukarno passed a law allowing him to ban parties whose ideologies conflicted with those of the state, or whose members rebelled against the state, and he subsequently used this law to threaten Masyumi to either dissolve itself or be forcefully dissolved. Following the collapse of the rebellion, Natsir and Sjafruddin, along with other senior Masjumi figures, were jailed in January 1962.
