BEIRUT (AP) — Activists say Syrian regime forces are shelling suburbs of the capital of Damascus on the third day of what was meant to be a four-day holiday cease-fire. They say government troops and rebels are also clashing in several areas of the country.

A U.N-backed truce declared for the Muslim holiday of Eid al-Adha has largely unraveled. Activists say more than 150 people were killed Friday, the start of the holiday, and more than 120 people on the second day, on par with previous daily casualty tolls.

The Britain-based Syrian Observatory for Human Rights says government troops shelled three suburbs east of Damascus on Sunday. Another opposition group also reported violence there. Activists say fighting also resumed in the city of Aleppo and near a northern military base.