DAMASCUS (AFP/Reuters) - Security forces killed at least three people as they opened fire on protesters who rallied in their tens of thousands across Syria on the last Friday of Ramadan, vowing again to bring down the regime. A fourth man died Friday in detention, his family told rights groups. Spurred by calls posted on the Internet, protesters flooded the streets in the north, centre and south of the country, chanting "Bashar, we don't love you, even if you turn night into day," according to activists. The latest bloodletting came as the UN Security Council remained divided over measures against President Bashar al-Assad's regime, with Russia and China blocking bids to pass fresh sanctions, including a total arms embargo. The ruler of energy-rich Qatar, Sheikh Hamad bin Khalifa Al-Thani, meanwhile, upped the pressure on Syria during a visit to key Damascus ally Iran, saying the use of force was "fruitless." Meanwhile, UN diplomats said that the US and European push to impose UN Security Council sanctions on Syria for its bloody crackdown on pro-democracy demonstrators is meeting fierce resistance from Russia and China. The United States, Britain, France, Germany and Portugal circulated a draft resolution that calls for sanctions against Syrian President Bashar al-Assad, influential members of his family and close associates. They said they wanted to put the draft to a vote as soon as possible. Meanwhile, the first UN mission to be allowed into Syria since the government's brutal crackdown began in March found that civilians urgently need more protection and feel "under constant threat," the United Nations said on Friday. After months of refusals, Damascus agreed last week to let the UN team into the country and promised that it would have full and unfettered access to all sites, a pledge that UN spokesman Farhan Haq suggested was only partly kept. "A UN team has completed a humanitarian mission to Syria, which took place on Aug. 20 to Aug. 25," Haq told reporters.