An opposition leader said the secretary-general of the Gulf Cooperation Council was due in Sanaa tomorrow to try to resurrect a deal to end the crisis, which fell through last month when President Ali Abdullah Saleh - in power for 33 years - refused to sign. Yesterday security forces, using machine guns mounted on military vehicles, fired into the air, wounding dozens of protesters setting up roadblocks along a main street in the city 120 miles south of Sanaa. In the southern city of al-Baydah, angry protesters attacked the ruling party building and set it ablaze after two demonstrators were shot dead by men in civilian clothes believed to be security officers, residents said.