CAIRO (Update 2) - Egypt's Revolution Youth Coalition is demanding authorities investigate Friday's violence in Cairo's Tahrir Square that left two protesters dead. The coalition announced a news conference Sunday to reveal its future plans, but said it would postpone talks with the Supreme Council of the Armed Forces until the end of the probe, Bikyamasr.com reported Sunday. "The coalition will call for an open sit-in in Tahrir (Square) beginning next Friday if the council is not swift in the investigation and the trials," an unnamed member of the coalition told the al-Dostour newspaper, the Web site said. The Supreme Coalition of the Armed Forces late Saturday said it would break up protests in Tahrir Square, al Masry-al Youm said Sunday.