Morale is running low among fighters in northern province as regime forces gain ground.
Almost 93,000 people were killed in Syria’s conflict by the end of April this year, but the true number could be “potentially much higher”, the United Nations human rights office says.
The exact figure released on Thursday – 92,901 people – is much higher than the UN’s last death toll back in January of 59,000 people.
“The constant flow of killings continues at shockingly high levels,” said Navi Pillay, the UN high commissioner for human rights. “This is most likely a minimum casualty figure. The true number of those killed is potentially much higher.”
An average of more than 5,000 people have been killed every month since last July, while rural Damascus and Aleppo have recorded the highest tolls since November, the report said in its latest study compiling documented deaths.
Among the victims were at least 6,561 children, including 1,729 children younger than 10.
The UN has acknowleged it has “underreported the number of deaths”.
Rupert Colville spokesman for Pillay, told Al Jazeera that there were huge constraints on estimating the number of people who had died in the conflict.
“We’re reliant, really, on some very brave activists who since the beginning of this conflict have done there best to keep track of how many people have been killed,” Colville said.
The report said UN teams on the ground and activists had found evidence of children being tortured during the conflict.
“We’ve all seen videos and photos of children who have been tortured to death, children who have been summarily executed, ” Colville said.
“We’ve seen entire families that have been slaughtered, including babies even, and then you’ve got children who have been killed by indiscriminate shellfire, missiles, aerial bombardment and a general, no-holds-barred conflict.”
Meanwhile, Syrian rebels reportedly killed at least 60 people, including civilians government loyalists, in a battle in Halta, a Sunni-majority village in the country’s east, activists said.
The fighting over the past few days targetted members of the Shia community, highlighting the increasingly sectarian nature of the country’s civil war.
The opposition fighters reportedly stormed and burned civilian homes in the village in the eastern Deir Azzor province.
The attack is said to be in retaliation for an earlier assault by Shias from Hatla that killed four opposition fighters.
US debates strategy
A Syrian government official denounced the attack on the Shia-section of the Sunni-majority Hatla village as a “massacre” of civilians, the Associated Press news agency reported on Thursday.
A video posted online by rebels on Tuesday, entitled “The storming and cleansing of Hatla”, showed dozens of fighters carrying black flags celebrating and firing guns in the streets of a small town as smoke curled above several buildings.
Most armed rebels in Syria are from the country’s Sunni majority, while President Bashar al-Assad has retained core support among the minorities, including his own Alawite sect, an offshoot of Shia Islam, along with Christians and Shia.
The alleged massacre came as the US again debated how to help the Syrian opposition.
Addressing reporters with his British counterpart William Hague in Washington, US Secretary of State John Kerry said on Wednesday that a political solution that would end the war and save Syria was still being sought.
The US has weighed for months whether to give arms to the rebels, but the issue is now firmly on the table given increased involvement by Hezbollah, the armed Lebanese Shia group, and as Iran backs President Assad on the battlefield.
The talks came as regime forces were reported to be preparing for a major offensive on rebel-held parts of the northern city of Aleppo.
The Obama administration is meeting this week on whether to arm the Syrian rebels, a topic that Kerry said he discussed with Hague.
The meetings come ahead of a G8 summit in Northern Ireland next week.
G8 leaders are expected to discuss a co-ordinated response to the Syrian conflict, and how to bring the rival sides together at a peace conference.