An engineering graduate from a well-to-do family from Bhatkal, Karnataka, Yasin was relatively unknown till 2008, when his name cropped up during investigations into the blasts in Delhi, Ahmedabad, Surat, Bangalore and Hyderabad.
After the Mumbai crime branch arrested 21 Indian Mujahideen (IM) operatives in September 2008, its co-founders Riyaz and Iqbal Bhatkal fled to Karachi, and Yasin started running its operations in India, sources said, which included scouting across India for recruits for IM. His success in indoctrinating youngsters from Darbhanga, Bihar, came to light after several IM operatives were held in 2011.
He was caught with counterfeit currency in West Bengal in 2010, but he identified himself as Shahrukh and jumped bail. In November 2011, he evaded capture in Chennai.
Agencies believe Yasin is in India, but sources said he has visited Nepal and Bangladesh - one reason why a red-corner notice has been issued.