BELGRADE -The Syrian regime rained rockets and bombs on Eastern Ghouta Thursday, killing another 36 civilians as international pressure mounted to stop the carnage in the rebel-held enclave.
Calls for a humanitarian truce in one of the bloodiest episodes of Syria's seven-year conflict went unheeded as the death toll for Damascus's five-day blitz rose past 400.
UN chief Antonio Guterres said the aerial bombing campaign had turned Eastern Ghouta into "hell on earth", while German Chancellor Angela Merkel called for an end to the "massacre".
Residents huddled in basements as government forces pounded the besieged enclave with rockets and bombs, turning towns into fields of ruins and even hitting hospitals.
Aid group Doctors Without Borders said 13 of the facilities it supports in Eastern Ghouta were damaged or destroyed in three days, leaving remaining staff with very little to save the hundreds of wounded brought to them every day.
In the hospital mortuary in Douma, the main town in the enclave just east of Damascus, bodies wrapped in white shrouds were already lining up on the floor, two of them children.
Little pools of blood dotted the way to the hospital, where most of the victims of the sustained rocket fire unleashed by government troops on Thursday were taken.
- Nowhere safe -
"The rocket fire hasn't stopped this morning. Around 200 ground-to-ground rockets struck Douma alone," said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights, a Britain-based war monitor which relies on a network of sources on the ground.
Morning rain appeared to initially keep warplanes away but the sky cleared by midday and jets, some of them Russian according to the Observatory, soon returned.
Russia has so far denied direct involvement in the assault on Ghouta but the pro-government Syrian newspaper Al-Watan reported on Thursday that Russian warplanes and advisers had joined the battle.
Regime and allied forces have been massing around the enclave, in which an estimated 400,000 people live, ahead of a likely ground offensive to flush out holdout Islamist and jihadist groups.
"We are 14 women and children living in a room that is 10-feet wide, with no toilet and nowhere to wash," said 53-year-old Umm Abdo, who joined a large group in the basement of a school in Arbin.
The brief respite provided by the rain on Thursday encouraged some residents to venture out of their basements and shelters, to buy food, check on their property or enquire about their relatives and neighbours.
In the town of Hammuriyeh, a queue had formed outside a shop as starving residents tried to stock up but another rocket sowed panic and sent everybody back to their shelters.
In Douma, a young boy tried to peddle lighters on the street but rocket fire quickly forced him to scamper back to cover.
- Powerless -
An AFP correspondent saw rescuers known as the "White Helmets" forced to stop their efforts to retrieve a wounded woman from the rubble of a collapsed home when air strikes resumed.
When they ventured back to the site, the woman was dead.
Eastern Ghouta is controlled by jihadist and Islamist groups but many civilian areas and even hospitals were targeted this week.
The indiscriminate bombardment and the strikes on medical facilities sparked global outrage but few concrete options emerged to stop the bloodletting.
"The killing of children, the destruction of hospitals -- all that amounts to a massacre that must be condemned and which must be countered with a clear no," Merkel said.
Russia has asked for a special meeting of the UN Security Council and the Red Cross has demanded it be allowed to enter the besieged enclave to help overwhelmed doctors and nurses to treat the wounded.
The aid community voiced its frustration as the world appeared once again powerless to stop a conflict that has left almost 350,000 dead in seven years and caused destruction rarely seen since World War II.
Humanitarian agencies are "sickened that no matter how many times they've raised the alarm, taken the step of speaking out, called on the Security Council to do something, the violence and brutality will sink to new lows," a statement by the Syria INGO Regional Forum said.
Talks for a deal between the regime and the armed groups controlling Ghouta appear to have stalled.
Moscow on Thursday said fighters in Syria's rebel-held enclave of Eastern Ghouta had rejected Russia's offer to evacuate peacefully and were using civilians there as human shields.
The US, rights groups and pro-government Syrian press have said Russia is taking part in air strikes that have killed more than 350 people in the enclave over five days, but Moscow has denied the claims.
"A few days ago, our military in Syria suggested to the fighters that they withdraw peacefully from Eastern Ghouta, like the evacuation of fighters and their families that was organised in East Aleppo," Russian Foreign Minister Sergei Lavrov said during a press conference in Belgrade.
"The Al-Nusra Front and its allies categorically rejected this proposal and continue to shell the city from their positions, using the civilian population of Eastern Ghouta as a human shield," he said.
Lavrov added that Russia was ready to consider a UN Security Council draft resolution demanding a 30-day ceasefire in Syria as long as it did not include the Islamic State jihadist group or the Al-Nusra Front, Al-Qaeda's one-time Syria affiliate.
- 200 weapons -
The Russian military has fought a campaign for over two years in Syria, launched in September 2015 in support of Assad, helping to turn around the multi-front war.
Russia has tested over 200 new types of arms in Syria during its campaign in support of President Bashar al-Assad, a senior lawmaker said Thursday, as Moscow was being accused of taking part in the deadly air strikes.
"As we helped the brotherly Syrian people, we tested over 200 new types of weapons," said Vladimir Shamanov, a former commander of Russia's airborne troops who now serves as head of the Russian Duma's defence committee.
"It's not an accident that today they are coming to us from many directions to purchase our weapons, including countries that are not our allies," he said.
"Today our military-industrial complex made our army look in a way we can be proud of," he said.
Shamanov's remarks also come amid reports that Russia has deployed its Su-57 stealth fighter prototype in Syria, where two such planes were reportedly spotted Wednesday.
Photos of the fifth generation jet, allegedly over Syria, were re-posted by various state media Thursday.
A source in the defence ministry confirmed to RBK news agency that the two planes were sent to the Hmeimim base "for a test in real conditions."
Kremlin spokesman Dmitry Peskov declined to comment on the reported deployment of Su-57.
Russia has been accused of indiscriminate bombing throughout the conflict causing massive casualties.
The focus is now on the air strikes against Eastern Ghouta, where the death toll for five days of bombardment by the Syrian regime and its allies passed the 400 mark, a monitor said on Thursday.
"Five days of air strikes and intense artillery fire by the regime and its Russian ally have killed 403 civilians, including 95 children," the Syrian Observatory for Human Rights said.
The head of the Britain-based Observatory, Rami Abdel Rahman, said 46 people were killed in strikes and rocket fire on Thursday.
Bodies of victims killed earlier in the week were also retrieved from the wreckage of destroyed buildings, bringing the overall death toll to 403.
The armed groups in Ghouta have also fired rockets and mortar rounds on civilian areas in the capital, which is under government control, killing at least 16 over the same period.