"All hospitals in eastern Aleppo out of service"

All hospitals in opposition-held eastern Aleppo are out of service after days of heavy air strikes on the besieged area of the Syrian city, its health directorate said late on Friday. A war monitor, however, said some were still working.

Syrian opposition fighters fought fiercely with pro Bashar al-Assad forces trying to advance into opposition-held areas of eastern Aleppo and warplanes kept up their bombardment of the area on Friday in a powerful bid by Damascus to retake the entire city.

United Nations humanitarian adviser Jan Egeland said the population of eastern Aleppo faced a "very bleak moment" with no food or medical supplies, winter approaching, and increasingly fierce attacks by the Syrian regime and allied forces.

"This destruction of infrastructure essential to life leaves the besieged, resolute people, including all children and elderly men and women, without any health facilities offering life-saving treatment [...] leaving them to die," said the health directorate's statement sent by an opposition official late Friday.

Elizabeth Hoff, the World Health Organization representative in Syria, said a UN-led group of aid agencies based over the border in Turkey "confirmed today that all hospitals in eastern Aleppo are out of service."

Bombs hit a hospital in east Aleppo on Friday evening, the fourth health facility put out of service there in four days, the Syrian Observatory for Human Rights, a Britain-based war monitor and a health official from a rebel area said.

The Observatory said some hospitals were still operating in parts of eastern Aleppo but that many residents were frightened to use them because of heavy shelling.

Medical sources, residents and opposition fighters in eastern Aleppo say hospitals have been damaged in recent days by air strikes and helicopter barrel bombs, including direct hits on the buildings. Health and rescue workers have previously been able to bring hospitals put out of service by air strikes back into operation but a lack of supplies is making that harder.

Mohamad Abboush, an east Aleppo resident, said an air strike killed two of his relatives, a 45-year-old uncle and a 12-year-old cousin, on Friday morning. As they sought out medical care for other relatives wounded in the attack, he said they found one hospital in ruins and another in flames.

"The whole of Aleppo is being bombed," he said.​

The children's hospital was also hit on Thursday while it was struggling to treat people affected by an earlier chlorine attack, said the Guardian. The staff was left helpless as it had to evacuate while doctors were treating victims struggling to breathe because of chlorine exposure.

"We are moving the children's hospital because it has been hit twice this week and is considered a full-on target," the Independent Doctors Association told the Guardian. "We took the decision to evacuate it today, to relocate the staff and patients elsewhere."

The battle for Aleppo

Intense air strikes have battered eastern Aleppo since Tuesday when the Syrian regime and its allies resumed operations there after a pause lasting weeks. Ground operations against opposition positions on the front lines started on Friday.

Both the Free Syrian Army and regime officials have confirmed mobilisation on a large-scale level by Assad's forces to take Aleppo.

Syrian state television said on Tuesday the air force had targeted "terrorist strongholds and supply depots" in Aleppo. Russia has said its air force is only conducting air strikes in other parts of Syria. The regime, operating out of Damascus, describes all the opposition fighting it as terrorists.

The battle for Aleppo is now the central focus of a five-and-a-half-year-old civil war, which is potentially entering a new phase after the election of Donald Trump as US president. While Trump's Syria policy has not been fully spelt out, he has suggested Washington could re-examine its longstanding opposition to Russia's support for Assad.