BEIRUT — Aid officials rushed to evacuate more women, children and elderly from rebel-held areas that have been blockaded by government troops for more than a year in Syria’s third-largest city, Homs, after a U.N.-brokered cease-fire was renewed for three more days Monday.

The truce, which began Friday, has been shaken by continued shelling and shooting that prevented some residents from escaping and limited the amount of food aid officials have been able to deliver into the besieged neighborhoods.

U.N. humanitarian chief Valerie Amos sharply criticized the two sides, saying U.N. and Syrian Red Crescent workers were “deliberately targeted.”

The drama in Homs, where Amos said around 800 civilians have been evacuated so far, played out as activists Monday reported new sectarian killings in Syria’s civil war.

Al-Qaida-inspired rebels killed more than two dozen civilians, including an entire family, when they overran a village populated by minority Alawites on Sunday, Rami Abdurrahman of the British-based Syrian Observatory for Human Rights said. They also killed around 20 local fighters in the village, he said.

The violence further rattled peace talks that entered their second round Monday in Geneva – and which quickly became mired in recriminations between President Bashar Assad’s government and the opposition in exile.

The two sides’ first face-to-face meetings adjourned 10 days ago, having achieved little. This time, the two appeared even further apart, with no immediate plans to even sit at the same table. U.N.-Arab League envoy Lakhdar Brahimi was holding separate talks with each side.