A Syrian commander close to President Bashar al Assad defected to Turkey, reports said.
Brig. Gen. Manaf Tlass, one of Assad's closest confident, left Syria and sought refuge in Turkey.
He is now believed to be traveling from Turkey to Paris to attend the Friends of Syria conference and meet opposition leaders.
If confirmed, it would be the first time a close adviser to the president left the regime as a consequence of the Syrian conflict.
Despite a 16-month-long uprising against the regime and over 10,000 casualties, Assad's close circle of family and advisers has remained largely loyal , so Tlass' departure could be the first real sign cracks at the high level are starting to appear.
"Manaf is one of the regime's main figures," Bashar al-Heraki, a member of the Syrian National Council, the umbrella political group in exile to the New York Times.
Heraki said General Tlass would soon make his defection public with an announcement but declined to confirm he was in Turkey.
"It is a negative sign for this regime," Mr. Heraki was quoted as saying. "It has started to lose control."
Col. Riad al-Assad, the head of the Free Syrian Army in Turkey told Al Jazeera Tlass had fled to Turkey.
The Britain-based Syrian Observatory for Human Rights said three of their Syrian contacts on the ground said Tlass had left the country but could not confirm he had defected.
His departure comes as about 100 delegations are meeting Friday in Paris at a so-called Friends of Syria conference, aimed at bolstering the Syrian resistance and pressing Syria's allies to discuss transition strategies for the embattled country after 16 months of brutal crackdowns and civil war.
Who is Manaf Tlass?
Tlass is the son of a prominent general and close advisor to the Assad family, Mustafa Tlass.
Mustafa Tlass was defence minister under both Assad and his father Hafez. He was appointed to the post in 1972 until 2004.
He was especially close to president Hafez al Assad and is said to have been influential in helping him shape the authoritarian regime that still prevails today.
A Sunni Muslim, Tlass was often cited as an example Hafez al-Assad's regime-made up of a majority of Alawite, a Shia sect which the Assad family belongs to- was not sectarian in essence.
Tlass is also said to have helped Bashar al-Assad become an authoritative figure in the Syrian regime after his brother Basil, who was expected to become Hafez's successor, died in 1994.
Tlass two sons, Firas and Manaf benefited from their father's privileged position in the Assad's inner circle.
While Firas became a business tycoon, Manaf forged a career in the army.
Manaf became close to Bashar and the two were often seen eating together in Damascus.
"He's a close friend to Bashar," Mr. Heraki said. "So it is not only a strong strike against the regime, but the strongest message yet to Bashar that he is no longer safe, and a message to other officers thinking about defecting."
It is not clear why Manaf Tass left the country but sources in Damascus said the uprising put a strain on the relationship between the Tlass and Assad family.
Mustafa Tlass is said to have left to Paris in March, citing medical reasons and Tiras is 'pursuing business ventures' in the United Arab Emirates.
Manaf remained in Damascus where he was tasked with keeping the uprising in the capital's suburbs of Harasta and Douma under control. When he failed to do so, the regime became more and more suspicious, pouting further strain on Bashar and Manaf's relationship.
Sources close to him in Damascus even said he had been offered asylum by Saudi Arabia, but it seems he headed to Turkey instead.
Latest rumours suggested Tlass was heading to paris to attend the Friends of Syria Conference.