A man carries an infant rescued from the rubble of buildings on Monday, after government bombing in the rebel-held town of Hamouria, in the besieged Eastern Ghouta region, on the outskirts of the Syrian capital, Damascus. (Abdulmonam Eassa/AFP/Getty Images)

They were among the bloodiest days of Syria’s war. In a rebel-held Damascus suburb this week, doctors worked around the clock. Families huddled across basements and bedrooms, sticking close together so they didn’t die alone.

Almost 300 people have been killed in the Syrian government's three-day blitz on Eastern Ghouta, war monitors said, with warplanes bombing densely populated areas and helicopters dropping barrels packed with shrapnel and crude explosives.

The effects, and images below, are shocking.

Casualties who made it to a hospital found a system pushed to breaking point. Doctors Without Borders said Wednesday that 13 of its medical facilities have been damaged since Sunday.

“There have been many massacres,” said Huda Kyayati, a relief worker with the Syrian nonprofit group Women Now for Development. “I cannot handle the idea of going down to the basement, because I cannot imagine what it would mean to be bombed and die under the rubble.”

Across much of Syria, this is no longer a civil war. As the conflict escalates, international powers, including the United States, Russia, Turkey and Iran, are scrambling for influence, clashing in the skies and on the ground. But in Eastern Ghouta, the final pocket of rebel territory around the capital, it is just the Syrian government that is clashing with the country’s armed opposition.

Trapped in the middle are as many as 400,000 people, most civilians.

Smoke plumes rise Tuesday after a regime airstrike in the rebel-held town of Hamouria. (Abdulmonam Eassa/AFP/Getty Images)

LEFT: A woman and children run for cover Monday after government bombing in Hamouria. RIGHT: A member of the Syrian Civil Defense, popularly known as the White Helmets, carries an injured child rescued from the rubble. (Photos by Abdulmonam Eassa/AFP/Getty Images)

Volunteers from the White Helmets search for injured victims in the rubble of buildings in Hamouria on Tuesday. (Abdulmonam Eassa/AFP/Getty Images)

A man carries an infant injured in an attack in Hamouria on Monday. (Abdulmonam Eassa/AFP/Getty Images)

Civilians look at the rubble in the wake of government attacks in Hamouria on Monday. (Abdulmonam Eassa/AFP/Getty Images)

Syrian troops laid siege to Eastern Ghouta in April 2013, sending prices soaring and causing dozens of deaths related to a lack of essentials.

The price of bread has risen to 1,500 Syrian pounds, according to monitoring groups. A few miles away in parts of the Syrian capital controlled by the government, it costs less than 100.

As the pace of death accelerates in Eastern Ghouta, so do preparations. Pathologists and gravediggers in the enclave said before the violence accelerated that they had 20 to 50 graves on standby at any given time. This week, they said that was not enough.

“We are overwhelmed. We are throwing body parts in mass graves. It’s all we can do,” said one man, speaking on the condition of anonymity because he feared retribution from the government in the event that it took full control of the area.

Medics across the enclave described grueling surgeries. One said he had removed a child’s eyes after they were shredded in an airstrike. Another said a colleague had found their nephew on the operating table.

Injured children are treated at a hospital in Douma, Syria, on Monday. (Mohammed Badra/European Pressphoto Agency)

A body of a child lies on the floor of a morgue in rebel-held Douma on Tuesday. (Mohammed Badra/European Pressphoto Agency)

The body of a girl is moved at a morgue in Douma on Tuesday, leaving a trail of blood. (Mohammed Badra/European Pressphoto Agency)

An injured child receives treatment Monday at a makeshift hospital in Hamouria. (Abdulmonam Eassa/AFP/Getty Images)

Unlike previous government attacks on the area, Tuesday’s bombardment did not target any specific neighborhood, according to the White Helmets.

As warplanes circled in the sky past midnight Tuesday, another volunteer for a Syrian nonprofit group, speaking on the condition of anonymity out of fears for his family's safety, said he had still not dared to take his children to the basement. “We might die here, but at least it won't be the darkness,” he said.

A Russian-made Syrian air force MiG-23 fighter jet flies over the rebel-held town of Arbin, in the besieged Eastern Ghouta region. (Amer Almohibany/AFP/Getty Images)

Zakaria Zakaria in Istanbul and Carol Morello in Washington contributed to this report.