Eighty-five Syrian soldiers, including a general and 14 other officers, fled into Turkey overnight with more than 200 family members, Turkish news media said.
The defections -- the largest single-day exodus from Syrian President Bashar Assad's army -- came as Syrian opposition figures gathered in Cairo to devise a unified strategy for pressuring Assad to step down as part of a solution to the 16-month-old bloody conflict the United Nations says has led to more than 10,000 deaths.
Some rebel groups and observers put the death toll at more than 14,000.
The defectors entered the town of Reyhanli in southern Turkey's Hatay Province as part of a group of 293 refugees "fleeing atrocities in Syria," Turkish state TV channel TRT Haber, the state-run Anadolu Agency and the independent English-language Turkish newspaper Today's Zaman reported.
Reyhanli, on Turkey's Mediterranean coast, has a large Sunni Arab population, in contrast with most of Hatay, whose Arab population are mostly Alawite. The Assad regime is made up of members of the country's minority Alawite sect, an offshoot of Shiite Islam. The majority of Syrians are Sunni Muslims.
The 14 other officers fleeing with their families Monday night included a colonel, a lieutenant colonel, four majors, seven captains and a lieutenant, Today's Zaman said.
Today's Zaman said the general was from a Syrian artillery division.
The Financial Times quoted activists close to the insurgent Free Syrian Army as saying a general who defected was associated with non-conventional weapons.
It was not immediately clear if this was the same general Today's Zaman cited.
The U.S. State Department says Syria has chemical weapons, allegedly including a large arsenal of nerve gas.
The activists told the Financial Times they expected the general would help them restructure the leadership of the rebels.
"He has a lot of information about the deployment of security forces and the regime's assets," an activist told the newspaper.
The general, whose name is likely to be made public in the next few days, is thought to have left his post last month and gone into hiding before being smuggled to Turkey, the Financial Times said.
Turkey, a former close Syrian ally, permits the 11-month-old Free Syrian Army -- made up mostly of former Syrian army personnel -- to operate from bases inside the Turkish border.
Turkey houses more than 35,000 Syrian civilians who sought refuge from the conflict.
News of the defections came as 250 members of Syria's fractious opposition movement met in Cairo to try to develop a unified strategy for pressuring Assad to step down as part of a solution to the conflict.
A weekend meeting of major world powers convened by U.N.-Arab League special envoy Kofi Annan in Geneva, Switzerland, left open the possibility that Assad would be allowed to remain in power as part of a government transition plan.
In Cairo, Arab League Secretary-General Nabil al-Araby urged Assad opponents to put aside "any narrow differences or factional disputes" and seize the opportunity to provide the international community a single force it can rally around.
Annan deputy Nasser Kidwa told Assad foes unity was "not an option, but a necessity" if the opposition factions hoped to get the support of fellow Syrians and aid from abroad.