Fact Box: Syria’s conflict
Syria’s conflict began in March 2011 and has left over 270,000 dead since then.
Syrian opposition groups want President Bashar al-Assad to resign.
Over four million have fled but nearly 18 million still live in Syria.
In September 2013, UN confirmed chemical weapons had been used in Syria.
In early 2014, ISIL fighters began taking over large parts of the country.
Russia has been supporting Assad's forces with air strikes since September 2015.
At least 20 people have been killed in air strikes in the northern Syrian city of Aleppo, a monitoring group has said.
The UK-based Syrian Observatory for Human Rights (SOHR) said on Wednesday that at least 10 people were killed in strikes targeting the Bayan hospital in a rebel-held part of Aleppo city.
Nine newborns were removed from their incubators after the aerial assault that also damaged equipment, according to the Independent Doctors' Association in Syria, which runs the hospital.
"There are only a handful of functioning incubators left in Aleppo," Dr Hatem, director of the hospital, said.
"Our ability to provide even the most basic protections to our most vulnerable is disappearing. Every world leader must imagine that one of these newborns were their own son or daughter.
"Whatever they would do to protect their own children they need to afford the same protection for ours."
In al-Marjeh neighbourhood, at least four people, including two children, were killed when government helicopters dropped barrel bombs.
One more person was killed in an air strike in the nearby neighbourhoud of al-Moadi, the SOHR added.
Zouhir al-Shimale, a local journalist, told Al Jazeera that the hospital is located on a very busy street.
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"There is a vegetable market on that street. It is a very busy area. At least four barrel bombs were dropped by government helicopters. So far the death toll we have received is 10, with another 30 people injured.
"In addition to that, air strikes have targeted al-Salhin neighbourhood, one person has been killed and several others have been injured. In al-Rashdin neighborhoud, an air strike left one woman killed," al-Shimale said.
'Distressed and paralysed'
At least 17 medical facilities have been attacked in the past two months, according to independent reports, and there are now only seven hospitals left functioning in Aleppo.
“After a week of intense attacks that have left dozens of civilians killed, Aleppo is now facing its first taste of siege," said Dr Osama Abo al Ezz, a surgeon from the Syrian American Medical Society working in Aleppo.
"We are distressed and paralysed. Yet international demands for civilian protection are not being backed up by any tangible action.”
Elsewhere in Aleppo province, the SOHR reported that Islamic State of Iraq and the Levant (ISIL, also known as ISIS) fighters have retreated from several villages as heavy clashes continue between the group and the predominantly Kurdish Syrian Democratic Forces (SDF).
|There have been 600 strikes on Aleppo this week, according to independent reports [Reuters]
The SDF, a US-backed coalition of Kurdish and Arab fighters, is headed by the Kurdish People's Protection Units.
Last week, the SDF launched an offensive to capture the town of Manbij, a suspected supply route for ISIL to smuggle weapons in from Turkey.
Separately, the observatory said last week that the US had air-dropped weapons to rebel fighters in Aleppo province, who have been battling ISIL.
"Aleppans' options are running out," said Dr Samah Bassas, CEO of the Syria Relief Network.
"The bombs we are used to. But if we are to be held under siege, hunger and disease will quickly take hold. Even more death is inevitable. The Russian and Syrian planes attacking us every day must be stopped."
Syria's conflict started with mostly unarmed demonstrations against President Bashar al-Assad in March 2011.
It has since escalated into a full-on civil war that has killed at least 270,000 people, according to the observatory.
Source: Al Jazeera