Senior U.N. Official Due in Syria as Forces Scramble to Scrub Signs of Assault BEIRUT, Lebanon - With the Syrian military's wholesale assault on the central city of Homs over, antigovernment protests descended into skirmishing in several towns and cities across the country on Tuesday, while opponents and supporters of President Bashar al-Assad traded barbed remarks about ending the violence. At the United Nations, the five permanent members of the Security Council and its Arab member, Morocco, began consultations on a new resolution on Syria as Valerie Amos, the United Nations humanitarian coordinator, was scheduled to arrive in Damascus on Wednesday. But Mr. Assad's government seemed determined to scrub as many signs of its monthlong assault as possible from Homs before showing it to the world. Reports of violent mopping-up operations continued to filter out from the city, especially widespread arrests and periodic executions, mostly of young men. In a sign of faltering confidence, China said on Wednesday that it was withdrawing workers from Syria, apparently seeking to forestall a repeat of the chaotic exodus of some 36,000 Chinese laborers from Libya in the fighting that led to the fall of Col. Muammar el-Qaddafi last year, Reuters reported. Only about 100 Chinese workers will be left behind to guard work camps and equipment, Minister Chen Deming said, without giving figures for the total number of Chinese citizens or projects in Syria, according to Reuters. "The Chinese government and ministries must seriously undertake the protection of Chinese firms" production and projects overseas, and the protection of the lives of Chinese citizens overseas, especially engineering teams," Mr. Chen told reporters. The Chinese move offered a sharp contrast to the government's efforts to enforce its writ. "The government has control over Homs again," said a 50-year-old Homs resident who had managed to flee to safety in Beirut. They are arresting many people. Empty buses were seen moving into neighborhoods, then leaving filled with young men and boys, she said. A grainy, shaky video of soldiers walloping young men as they pushed them onto what appeared to be a green military bus was shown on Al Jazeera, the Arabic satellite channel, but it was not clear where or when the footage had been taken. The mopping-up operations also seemed aimed at clearing up pockets of resistance; the Homs resident said helicopters had been seen flying low over the city, followed by explosions. The government and the opposition accused each other over a massacre whose 18 victims were shown on Addounia, a Syrian satellite television station, with gruesome details of the fatal gunshot wounds. On the wall behind the men a message in pale script, purportedly signed by the Free Syrian Army, an anti-Assad resistance force, said that the deaths were the fate of all collaborators. But the opposition said the victims, named in a press release from the Syrian Network for Human Rights, had been killed by the government and were all members of at least three families in the Sabuh clan. A convoy bearing aid from the International Committee of the Red Cross was blocked from entering the embattled Baba Amr neighborhood of Homs for a fifth day, while Syrian state television boasted about the immense cleanup operation. Bulldozers were shown pushing aside piles of rubble from heavily pockmarked buildings while residents were filmed sweeping the streets. "Thank God the Syrian Army came so we can return to our homes," crowed one woman, while most of the interviews that were shown featured people making disparaging remarks about the "armed terrorist gangs" that they said held them hostage during the siege. Residents who fled in recent days spoke of the smell of death and piles of garbage drifting like snowbanks, casting a pall over the city. "When we fled there were still dead bodies on the floor," said a 62-year-old great-grandmother who fled Homs for Tripoli, Lebanon. "We had to leave them all," she added. It smelled of blood, destroyed houses and ruins. There were dead people under the ruins of buildings. Elsewhere in Syria, fatal clashes were reported in neighborhoods in the southern city of Dara'a, the font of the year-old Syrian uprising, where tanks and other heavy weaponry firing into a residential neighborhood had killed five members of one family and grievously wounded a sixth, opposition activists said. An employee of The New York Times contributed reporting from Beirut, Michael Schwirtz from Moscow, and Alan Cowell from London.