2 Syrian colonels killed by gunmen (AP) BEIRUT - Gunmen struck Thursday in the heart of Syria's largest city and a stronghold of support for President Bashar Assad, killing two army colonels at a downtown roundabout in an attack that state media blamed on terrorists. Separately, in the central province of Hama, rebels attacked an army truck and killed two soldiers, activists said. Fresh clashes also broke out between government troops and army defectors in the country's north and south, they said. The violence came as Arab leaders meeting at a Baghdad summit struggled with deep divisions about how to address Syria's crisis. The leaders are expected to pass a resolution calling for a cease-fire and an immediate, daily two-hour stop to fighting across Syria to permit aid to suffering civilians. Such a resolution would fall short of previous calls by the body that Assad give up power, but would back efforts by U.N.-Arab League envoy Kofi Annan to broker a political solution. Syria's state news agency said four gunmen belonging to an "armed terrorist group" opened fire on the two colonels in the Bab al-Hadid roundabout in the center of Aleppo, the country's largest city. The high-ranking officers, identified as Abdel-Karim al-Rai and Fuad Shaban, were on their way to work. No one immediately claimed responsibility for the attack. The Syrian government blames the uprising on terrorists carrying out a foreign conspiracy. The anti-Assad uprising has become increasingly militarized since it started last March, but Aleppo has largely been spared clashes between government forces and rebels. However, two mysterious bombings in the city this month killed 29 people. No group claimed responsibility for the attacks. The U.N. says more than 9,000 people have been killed since Syrians first took to the street last year to call for political reforms. Assad's security forces deployed tanks, snipers and pro-regime thugs to quash dissent, and the protests spread. Many in the opposition have also taken up arms to defend their communities and attack government troops. A flurry of international diplomacy has failed to stop the violence. The U.S., Europe and many Arab countries have called on Assad to leave power, and the U.N. and the Arab League have appointed former Annan, a former U.N. chief, to try to broker a solution. In Thursday's attack on the army truck in central Hama province, the Britain-based Syrian Observatory for Human Rights said rebels killed two government soldiers who were being taken north of the provincial capital, Hama. The group also said at least three civilians were killed Thursday in army raids on rebellious villages in the Idlib province along Syria's northern border with Turkey. It also reported clashes in the southern town of Dael. An activist in the town said that residents woke up to a huge explosion followed by intense gunfire. He said the fighting, as well as government snipers, have kept civilians pinned in their homes. "The security situation is very hard, with snipers on the roofs," Adel al-Omari said over the phone. It is very dangerous here and you can't leave your house. Anyone who moves is targeted. The Observatory said eight government soldiers were wounded in the Dael clashes. Activist claims could not be independently verified. The Syrian government rarely comments on clashes and has barred most media from working in the country.