Nearly 180 people, including 51 children, have been killed in Syria's Eastern Ghouta in just over two weeks, the volunteer White Helmets rescue group said Sunday, as the government steps up its air raids on the country's remaining rebel-held areas.
The death count was announced as more regime strikes were reported over the weekend and as activists posted videos online of rescuers pulling children from the rubble of targeted buildings.
The start of the year has been marked by death and destruction in Eastern Ghouta, an enclave the outskirts of the capital Damasus.
The area is rebel-held but has been besieged by government forces for more than four years. The Syrian government, backed by Russian air power, began an offensive to retake it on December 29 last year. The White Helmets said Sunday that the offensive had involved hundreds of airstrikes, missiles and cluster bombs.
The group said that 177 people had been killed in the latest offensive, and more than 800 civilians, including at least 200 children, had been injured.
UNICEF, the UN's agency for children, said that 30 children had been killed in the first two weeks of the the year, and that 200,000 children had been trapped there since 2013.
"It is shameful that nearly seven years into the conflict, a war on children continues while the world watches. Millions of children across Syria and in neighboring countries have suffered the devastating consequences of unabating levels of violence in several parts of the country," UNICEF said in a statement Sunday.
"UNICEF received information from inside east Ghouta that people are taking shelter underground in fear for their lives. One particular heavy attack on residential buildings was so strong it reportedly injured 80 civilians including children and women. Medical personnel struggled to pull survivors out of the rubble."
The White Helmets also reported a small-scale chlorine gas attack in the area.
CNN has not been able to independently verify the attack. The Douma Medical Center said it treated six people, including children, for symptoms consistent with chlorine poisoning.
Eastern Ghouta is a designated "de-escalation zone" under a ceasefire deal brokered by Russia, Turkey and Iran, which Syrian President Bashar al-Assad agreed to last year. Violence by the regime and rebel groups is in violation of the ceasefire.
UN: Schools and hospitals targeted
Eastern Ghouta was seized by rebel groups after the Syrian civil war erupted. The government chokehold on the enclave has led to a desperate humanitarian situation there, with the regime repeatedly refusing to allow aid in -- or civilians to easily leave.
CNN has received reports from medical organization operating in the country that hospitals and other medical facilities are being targeted in Eastern Ghouta, as well as the provinces of Idlib, the largest-remaining rebel-held area, and Hama.
UNICEF said that the women and children's hospital in Idlib had been hit three times and taken out of service while schools were also being targeted.
"Two medical facilities came under attack in the past days in east Ghouta, and most health centers had to close because of the violence. In some areas, mobile emergency clinics are the only way for families to receive medical treatment and aid," UNICEF said Sunday.
"Schools have been reportedly closed in and around east Ghouta at a time when children elsewhere in Syria are sitting for their mid-term exams."
In late December, the government allowed more than 80 people to leave Eastern Ghouta to be taken to hospitals in Damascus for medical treatment, in a one-off people-swap deal, in which prisoners were exchanged for critically ill civilians.
A critically ill six-month-old baby died while waiting to be evacuated, according to Mohamad Katoub, advocacy manager for the Syrian American Medical Society.