On 8 January 1968, along with like-minded activists, Sikder formed a clandestine organisation named Purba Bangla Sramik Andolon (East Bengal Workers Movement EBWM) with an objective to lead a struggle against the revisionism of the existing "Communist" organisations and to form a revolutionary Communist Party.
1968年1月8日，斯卡德尔与志同道合的活动分子一起组成了一个秘密组织，名叫东孟加拉工人运动（Purba Bangla Sramik Andolon），其目标是领导与现有“共产主义”组织的修正主义斗争并形成革命共产党。