The Muttahida Majlis-e-Amal (MMA) has announced to hold a peaceful demonstration and sit-in outside Sindh assembly at 4.00 pm on Friday. The demonstration is being staged to lodge protest against the murder of MMA leader Aslam Mujahid, government's failure in arresting the assailants, worsening law and order situation in Karachi, a press release said on Thursday.