The opposition movement driving Syria’s 7-month-old uprising has mostly focused on peaceful demonstrations, although recently there have been reports of protesters taking up arms to defend themselves against military attacks. There have also been increasing reports of defections from the military, highlighting a trend that has raised fears that Syria may be sliding toward civil war.

The British-based Syrian Observatory for Human Rights said the clashes Monday pitting Syrian troops against army defectors left casualties on both sides, but there was no precise death toll. The fighting happened in Houla, which is comprised of several villages in the Homs province.

About 25 miles (40 kilometers) away in the city of Homs, security forces killed four people, the observatory said. Syria’s third-largest city, Homs has seen some of the most severe violence in the past months.

The Assad regime has banned most foreign journalists and prevented independent media coverage, making it difficult to confirm events on the ground. Activist networks with a wide network of sources on the ground and witnesses reached by telephone have provided a steady stream of information about the crackdown.