Doha, Qatar - In a letter addressed to the UN Security Council, more than 70 countries have demanded that Syria stop its air strikes and use of barrel bombs that have killed thousands of people.

The letter, which was sent on Thursday to Ban Ki-moon, the UN chief, and General Assembly, expresses "outrage" at the continuing violence against civilians, especially by the "systematic use of barrel bombs".

"May 2015 was reportedly the deadliest month of the Syrian crisis so far. In recent weeks helicopters of the Syrian air force repeatedly bombarded heavily populated areas in and around Aleppo, leaving hundreds of civilians dead and dozens of others wounded," the letter said.


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The countries urged the UN to recall all violations and abuses committed in Syria, adding that they may amount to war crimes and crimes against humanity.

"The Syrian authorities must cease indiscriminate aerial attacks. On behalf of our respective governments, we call upon the Security Council to advance its efforts related to ensuring the implementation of its existing resolutions on Syria and preventing the future use by the Syrian airforce of any such aerial bombardment".

Civilians targeted

On the ground, the Syrian Observatory for Human Rights reported on Friday the deaths of 10 civilians following a rocket attack by opposition fighters in Aleppo.

In addition to that, at least five civilians were killed and 10 others were injured in air strikes targeting opposition-held Al-Qaterji district in Aleppo city.

The UK-based monitor also reported that the Syrian government dropped barrel bombs on Damascus suburbs, Homs, Aleppo, Idlib and Deraa, killing at least nine people so far.

The Syrian conflict has left over 230,000 people killed and millions displaced since its outbreak in 2011 [Reuters]

The nine toll is still expected to rise.

On Thursday, activists told the Syrian Observatory that government forces dropped 20 barrel bombs on Damascus suburbs and Quneitra.

Sources told Al Jazeera that in Homs, one child was killed and several others have been injured during government air strikes on residential areas in Talbiseh, adding that barrel bombs were also used.

On Wednesday the Syrian government was accused of using 'elephant rockets' in Douma, located in the Damascus suburbs, killing dozens including children.

An activist in Douma told Al Jazeera that clashes have been occurring in Damascus suburbs since the rocket attack.

"We have over 100 people injured staying at hospitals following that attack, it was a horrific massacre. We have been hearing extremely loud and intense clashes taking place around us, especially on the Damascus-Homs road," he said.

"Surface-to-surface missiles were used on civilians, in their own homes. The areas targeted were residential areas. Some homes have been completely demolished, some even collapsed while residents were in them".

'Hospitals destroyed'

Medicins Sans Frontieres, an international organisation operating inside Syria, said two hospitals have been destroyed due to barrel bombs in the past 10 days.

Busra hospital in Deraa province was destroyed by barrel bombs on Monday and a medical centre in northern Aleppo belonging to the organisation was also bombarded with barrel bombs, MSF said on its website.

The Syrian conflict has left over 230,000 people killed and millions displaced since its outbreak in 2011.

The UN is expected to announce this week that the number of Syrian refugees have risen to four million refugees

 At least 36 people were killed in this week's attack on Douma, where the government is accused of using "elephant rockets" [Reuters]

Source: Al Jazeera