ALEPPO — Syria rejected Monday new peace envoy Lakhdar Brahimi's comments labeling the conflict a civil war, as fighting rocked the cradle of the uprising and the army pounded the key hub of Aleppo. At least 52 people were killed, including two children in shelling in Daraa, the birthplace of the revolution in southern Syria, a watchdog said, as the United Nations brought an end to its troubled observer mission. Brahimi, who has replaced Kofi Annan as the international pointman for Syria, warned Sunday that it was now a matter of ending rather than avoiding civil war after 17 months of bloodshed. “A civil war, it is the cruelest kind of conflict, when a neighbor kills his neighbor and sometimes his brother, it is the worst of conflicts,” the veteran Algerian diplomat told France 24 television. “There are a lot of people who say that we must avoid civil war in Syria, me I believe that we are already there for some time now. What's necessary is to stop the civil war and that is not going to be easy.” But Syria reacted angrily. “To speak of civil war in Syria contradicts reality and is found only in the heads of conspirators,” the foreign ministry said in a statement carried by the official SANA news agency. The veteran Algerian diplomat has also rejected criticism from opposition groups for refusing to say whether President Bashar Al-Assad must resign. Brahimi told the BBC that he was not ready to say whether Assad should step down despite widespread international condemnation of his government's crackdown on dissent. The Syrian Observatory for Human Rights meanwhile reported fierce fighting on the second day of Eid Al-Fitr, the holiday celebrated by Muslims around the world to mark the end of the holy month of Ramadan. It said clashes erupted between rebels and government troops in Daraa after several areas were shelled, killing 15 people, including two children. Government forces using combat helicopters, tanks and heavy artillery have also been carrying out “savage” attacks on Herak, the opposition Syrian National Council said. Fighting also flared in southern parts of Damascus as the army battles persistent pockets of resistance despite claiming it retook most of the capital last month. UN observers wound up their troubled mission Sunday amid a failure by world powers to agree how to respond to Assad's crackdown and bring peace to the strategic Middle East state. Its operations were largely suspended in June and observer numbers cut back in the face of the mounting violence, as both sides violated a ceasefire that was meant to have been the cornerstone of Annan's plan. In Helsinki, Russian Foreign Minister Sergei Lavrov on Monday warned against what he called imposing “democracy by bombs” and said the United Nations Security Council alone could authorize the use of force against Syria. Amid speculation of further defections, Syria denied that Foreign Minister Walid Muallem had announced on Twitter he had replaced Vice President Farouq Al-Shara, who the opposition claimed had tried to defect. SANA said the information was “wrong” and that Muallem did not have a Twitter account. Across the border, Jordan said four rockets fired from Syria fell in the north, wounding a four-year-old girl and sparking a letter of protest to Damascus. — Agencies