A U.S.-backed ceasefire appeared to be holding in Syria on Sunday, after deadly violence rocked the region, when hundreds of people were killed in the city of Suwayda. The violence marks the biggest challenge yet to the new government in Damascus that toppled Bashar al-Assad in December.

Sectarian violence erupted again in southern Syria as local Sunni Bedouin tribes fought armed factions for the Druze religious community. The Syrian government dispatched troops to restore order, and Israel launched airstrikes to protect the Druze.

The Syrian government announced a ceasefire Tuesday after it intervened to quell the deadliest outburst of sectarian violence since March, clashes that prompted Israeli airstrikes. The ceasefire, however,