Many Syrian dissidents are calling for more support for troops who have defected to protect anti-government protesters from the government's brutal crackdown.

The Free Syrian Army is widely considered one of the main opposition armed wings that is fighting government troops blamed for killing thousands of people in a bid to crush the nine-month protest movement.

However, the group's representatives have not been invited to the first meeting of the main political opposition - the Syrian National Council - being held in Tunisia.

Al Jazeera's Zeina Khodr reports from Turkey's southern border with Syria, where refugees of Syria's unrest have urged more parties to back the army defectors' fight against the government.