Hospitals in the Yemeni capital struggled to cope with hundreds of casualties Tuesday following the bloodiest single day in Yemen\'s nine-month uprising. At least 36 protesters -- including a 10-month-old girl and a 14-year-old boy -- were killed Monday, a day after more than 30 others were killed, as government forces fired on tens of thousands of protesters demanding Yemeni President Ali Abdullah Saleh resign. Nearly 1,000 people, mostly demonstrators, were wounded in the two days, overwhelmed medical personnel said. Witnesses said snipers stood on rooftops around Change Square, the epicenter of anti-regime protests in the Yemeni capital, Sanaa, shooting unarmed passers-by with anti-aircraft guns, rocket-propelled grenades and mortars. Government troops shelled areas held by soldiers who defected from the regime and supported the protesters, witnesses said. Mass defections from the military, as well as from Saleh\'s government, effectively rendered much of the country outside of the government\'s control. Opposition leaders, who late Monday promised a truce with the government to stop the violence, urgently called for blood donors and tried to ferry wounded people to hospitals outside Sanaa. Many wounds appeared to have been caused by high-caliber rounds fired into the crowds from antiaircraft guns, Britain\'s Guardian reported. Despite the opposition truce promise, some protesters vowed to continue demonstrating and several loud explosions were heard in Sanaa overnight. Diplomats and Yemeni politicians scrambled Tuesday to speed up a long-stalled transition plan under which Saleh would step down after 33 years in power. Saleh, in Saudi Arabia for medical treatment after a June assassination attempt, has backed out of signing a deal at least three times, including last week, when he balked at transferring power to his vice president -- which frustrated activists who escalated demonstrations without waiting for a political solution or the intervention of the international community, The Wall Street Journal reported. Washington and other Western governments condemned Yemen\'s security-force crackdown Monday and called on the country to abide by plans for a power-transfer deal.