Beirut: Syrian troops on Thursday clashed with armed men believed to be military defectors in a southern village and a northwestern town, killing at least 13 people in the latest sign that the 7-month-old uprising against President Bashar Assad is becoming increasingly militarised, activists said.

The troops stormed the northwestern town of Binnish with more than 50 vehicles and the sound of explosions and gunfire could be heard.

The London-based Syrian Observatory for Human Rights and another activist group, the Local Coordination Committees, said five people were killed.

Rami Abdul-Rahman, who heads the observatory, said six soldiers and two defectors were also killed today in the southern village of Harra in the Daraa province.

He said an army force appears to have been ambushed in Harra's main square. Villages and towns in the Daraa province, where the uprising began, have been a hotbed of anti-regime
protests from the beginning.

Binnish is part of Idlib a province, which borders Turkey, an area where there have been clashes between the military and army defectors for months. After months of mostly peaceful protests, the growing involvement of military defectors in confrontations has raised fears that Syria may be sliding toward a civil war.

The uprising against Assad's regime began in mid-March amid a wave of anti-government protests in the Arab world that toppled autocrats in Tunisia, Egypt and Libya.

Assad has responded with a fierce crackdown, which the UN says has left nearly 3,000 people dead.

Syria's opposition movement has until now focused on peaceful demonstrations, although recently there have been reports of protesters taking up arms to defend themselves against military attacks.