BEIRUT (AP) — Syria's military said Monday that it is determined to repel an attack on the government-controlled western part of Aleppo as it continued to battle insurgents in intense battles on the city's edge.

The military said in a statement that opposition fighters have killed 84 people, mostly women and children, since launching their offensive Friday. The Syrian Observatory for Human Rights opposition monitoring group estimates that 48 civilians, including 17 children and 61 pro-government fighters, have been killed since.

Rami Abdurrahman, the director of the Britain-based Observatory, which relies on a network of activists on the ground in Syria, said about 70 opposition fighters were killed in the fighting that included airstrikes on the frontline.

Amnesty International said the armed opposition offensive was "marked by indiscriminate attacks on civilian areas."

An insurgent alliance, known as the Army of Conquest and which includes an al-Qaida-linked group, attacked western Aleppo, aiming to breach a months-long siege on the rebel-held eastern side of the city.

They captured al-Assad district on the western edge of government-controlled Aleppo Saturday, and the village of Minian further north. On Monday, insurgent media reported that they repelled an attempt by government and allied troops to regain control of the village.

The Syrian military accused the insurgents of "criminal acts" that included an alleged attack of toxic gas that wounded several. But it said that won't dissuade its troops from continuing its war on terrorism.

The insurgents denied those allegations and also accused the government of using chlorine barrel bombs on civilians in rural Aleppo.

Neither side's claims could be independently verified.

Amnesty International said the use of chemical weapons, regardless of who is behind the attack, can never be justified and constitutes a war crime.

The rights group said insurgents showed a "shocking disregard for human lives," using imprecise explosive weapons in the vicinity of densely populated areas.

"The goal of breaking the siege on eastern Aleppo does not give armed opposition groups a license to flout the rules of international humanitarian law by bombarding civilian neighborhoods in government-held areas without distinction," said Samah Hadid, deputy director for campaigns at Amnesty International in Beirut.