Four generals who had defected from the Syrian army have arrived in Turkey, Anatolia news agency reports, citing local Turkish sources.
The four were among some 10 high-ranking army officers stationed in cities including Damascus, Homs and Latakia, who crossed the border into Turkey's southern province of Hatay to join the Syrian rebels, the state-run Turkish agency said.
Fahd al-Masri, an adviser for Syrian opposition group the Higher Revolutionary Council, told AFP six brigadier-generals had defected in the last 48 hours along with four colonels, a a lieutenant colonel, a major and a female lieutenant.
He said they were from the province of Idlib near the Turkish border, where Syrian troops have been reported massing this week, ahead of an expected large-scale offensive.
The military build-up has prompted concerns that Idlib could suffer the same fate as the Baba Amr neighbourhood of the central city of Homs, which was stormed by government troops on March 1 after a month of shelling.
Idlib is considered important because of the presence of a large number of Free Syrian Army members, particularly in the Japal al-Zawiya area.
Frightened by the possibility of an operation in Idlib, many Syrians have fled across the border.
With the latest wave of arrivals on Friday, the number of Syrians entering Turkey in one single day reached 234, Anatolia said, citing Yusuf Guler, the district governor of Hatay's Reyhanli village.
The arriving refugees are being placed in tent camps in Hatay, where members of the rebel Free Syrian Army, made up of deserters from the Syrian security forces, are also based.
There has been an influx in the numbers of civilians fleeing the country in recent weeks as Bashar al-Assad's regime intensified its crackdown on opposition neighbourhoods.
Around 800 Syrians crossed into Turkey over the last week, upping the figure for the past month to 2,500, officials told AFP on Thursday.
The total number since the unrest began a year ago stands at almost 12,000, but these are only the Syrians who have been registered by the authorities as they entered Turkey.
Turkish authorities are readying for a scenario involving the mass arrival of refugees and establishing a container city in Kilis, some 150km from the Hatay camps.