Human rights activists in Syria say security forces continued their crackdown against anti-government protesters on Wednesday in the flashpoint city of Hama as tanks rolled into the city. The activists and residents also said communications to the city had been cut off. There were no reports of casualties after three days of attacks killed more than 130 people across the country. Most of the deaths occurred in Hama, as security forces continue a crackdown against those opposed to President Bashar al-Assad. Earlier, the U.N. Security Council held further talks behind closed doors on how to respond to the crisis in Syria. It has debated a European-drafted U.S.-backed resolution that calls on Syria to stop assaulting its cities, implement political reforms and launch an impartial investigation into attacks on anti-government protesters. Russia, a longtime ally of Damascus, suggested for the first time that it would not oppose a U.N. resolution to condemn the violence. Moscow has long resisted any such measure by the Council, where it holds a veto. The U.N. high commissioner for human rights on Tuesday warned Syria that the world is watching developments there. Navi Pillay bluntly criticized what she called Mr. Assad's efforts to shield the brutality of its crackdown by banning most foreign news coverage and preventing a U.N. fact-finding mission from visiting. Meanwhile, the Rights groups have said Syrian forces killed at least 1,700 civilians since the largely peaceful uprising began in March.