AMMAN - Syrian helicopter gunships fired machine guns to disperse a large pro-democracy protest in the town of Maarat al-Numaan on Friday, witnesses said, a dangerous escalation of force at the end of a day in which 32 civilians were reported killed by Assad's forces across the country.The gunship use was the first reported use of air power to quell protests in Syria's uprising.RELATED:UK, France put forward UN resolution condemning SyriaSyrian army pushes into border town, state TV saysThe Syrian Observatory for Human Rights said that helicopters fired at the town after security forces on the ground killed five protesters, but said no killings were reported in the assault by the helicopters.Also on Friday, UN spokesman Martin Nesirky confirmed a report by Kuwait news agency KUNA that Secretary-General Ban Ki-moon had been trying to call Assad on Thursday but was told that the president was "not available."He added that Ban had been trying to speak with Assad all week but was unable to get through to him.Britain, France, Germany and Portugal have asked the UN Security Council to condemn Assad, though veto-wielding Russia has said it would oppose such a move. Denouncing the Syrian government's actions, the White House said Friday's "appalling violence" had led the United States to back the European draft resolution at the United Nations. "The Syrian government is leading Syria on a dangerous path," the White House said.Thousands of civilians have fled the violence into Turkey, fearing security forces' revenge for incidents in which 120 troops were reported killed this week.But protesters, refugees in Turkey and rights activists said some soldiers in the northwest had refused to shoot at protesters and fighting had broken out between loyalist and mutinous forces this week. Rights groups say over 1,100 civilians have been killed since March in the revolt to demand more political freedoms and an end to corruption and poverty.World powers have shown no appetite for any Libya-style military intervention in Syria because it sits on a major fault line of Middle East conflict, allied with Iran against nearby Israel. The Syrian leadership has shrugged off mild punitive sanctions imposed so far, and verbal reprimands from abroad.Assad, 45, has promised reforms, even while cracking down on unrest posing the gravest threat to his 11 years of iron rule.