CAIRO: Supporters of Egyptian presidential candidate Hazem Salah Abu Ismail joined the ‘Friday of one demand' demonstration today in Tahrir Square. They said they will arrange a sit-in until the constitutional principles document drafted by Deputy Prime Minister Ali al-Selmy is cancelled. The sit-in will last until April 2012 is announced as the deadline for Egypt's ruling military council to hand over power to a civilian authority, they said. Other demands include releasing all political detainees, including Alaa Abdel Fattah, and for the release of the “blind sheikh,” Omar Abdel Rahman, who is imprisoned in the United States.