Sanaa , Yemen ( CNN ) -- A Yemeni man injured in protests at Sanaa University died of his wounds early Wednesday morning , a medical official said . Mohamed Ali Mutlak , 24 , was among dozens of anti-government demonstrators wounded Tuesday when security forces fired into the air and shot tear gas into a crowd of tens of thousands of protesters who had massed in front of Sanaa University , witnesses said . Eight of them were still in critical condition , said Dr. Waseem Qurashi , head of the medical department at Change Square , Sanaa University . According to witness Ala ' a Al-Khowlani , at least 40 anti-government demonstrators were wounded and at least one of them was in critical condition . Other witnesses put the number of wounded as high as 67 . Protests took place across the country Wednesday , witnesses said , but there was no word of violence . Tens of thousands of anti-government demonstrators were outside Sanaa University . In Taiz , tens of thousands of protesters continued their sit-in protest , calling for Saleh 's ouster . Thousands were also in the streets of Ibb , Aden , Hodeidah , and Dhamar . However , the recent casualties drew condemnation . Amnesty International on Wednesday urged Yemeni authorities to `` end deadly night raids and other attacks on protests . '' `` This is the second time in three weeks that protesters have been killed in late night raids by the security forces in the capital , '' said Philip Luther , Amnesty International 's deputy director for the Middle East and North Africa . `` These disturbing heavy-handed tactics used with lethal effect against protesters must stop immediately . People must be allowed to assemble and protest in peace . '' Amnesty said about 30 people have reportedly been killed in Yemen in the `` ongoing unrest which began early last month . '' Mohammed Abulahoum , a senior government official , Wednesday condemned `` the acts of violence used by the police and the military last night against civilian protesters outside the university . `` There was no need for that force . This will only escalate the tension between both sides , '' he added . He also rejected the official government explanation that tribesmen had tried to sneak arms into a no-weapons zone . `` They had no arms with them and they had no intention of using arms , '' Abulahoum charged , saying he knows those tribesmen . Yaser Al-Hasani , one of the demonstrators , said security forces cracked down after students defied their orders not to take food and blankets into the protest area outside the gates of the university . The supplies were intended for the thousands of anti-government demonstrators who have camped out calling for Saleh to step down . In a statement e-mailed to reporters , the government blamed the violence on people who had tried to sneak weapons into a `` weapon-free area '' outside the university , then resisted arrest . `` The suspects resisted arrest and soon thereafter a gun fight broke out , injuring dozens of suspected militants , policemen and innocent bystanders , '' a government statement said . `` Panic from the shootings set off a raging stampede in the area . There is no official confirmation on casualties at this point . '' The government said early Wednesday that the situation was under control and that the Interior Ministry would investigate the incident . Yemen 's anti-government demonstrations are unfolding in a nation wracked by a Shiite Muslim uprising , a U.S.-aided crackdown on al Qaeda operatives and a looming shortage of water . High unemployment fuels much of the anger among a growing and impoverished young population . The protesters also cite government corruption and a lack of political freedom . Saleh , who has refused to step down , has said he will not run again for the presidency in the next election . CNN 's Christine Theodorou , Mohammed Jamjoom and journalist Hakim Almasmari contributed to this report .
NEW : Protests took place at locations across Yemen Wednesday . The protests were sparked by the death of a young man who was shot and killed in Sanaa on Tuesday. Mohamed Ali Mutlak , 24 , was critically injured Tuesday and died early Wednesday , a doctor says . Eight other people are still in critical condition , Dr. Waseem Qurashi says .