Image copyright Getty Images Image caption A man evacuates a child from a building following a reported barrel bomb attack in Aleppo last month. Other pictures of child victims of barrel bombs - most too graphic to show here - have been circulating on social media

People across the Arab world have been expressing solidarity with child victims of barrel bomb attacks in Syria - and opposing President Assad - with the hashtag "we are the child, you are the barrel".

Barrel bombs are made from oil drums, water tanks or other containers filled with explosives and scrap metal, and usually dropped by a helicopter. They have been widely criticised for causing indiscriminate destruction, and despite being banned by a UN resolution, they have resulted in thousands of deaths in the Syrian civil war, according to the Syrian Network for Human Rights. Western countries say that only the Syrian government of President Bashar al-Assad is capable of carrying out these attacks, and he controls the only viable air force in Syria - although he has denied knowledge of barrel bombs in a BBC interview.

The use of barrel bombs has escalated in recent days in Aleppo, according to the UN. Pictures that claim to show what the weapons do to child victims (which we haven't been able to verify - and which are mostly too graphic to show or link to) have started spreading on social media networks, under an Arabic hashtag which translates as: "we are the child, you are the barrel".

And the tag gives an insight into the broad coalition of individuals who now oppose Assad in the region.

One of the first people to tweet the hashtag was Mahmoud Owaimer. As a Palestinian living in Gaza, Mahmoud told BBC Trending that the suffering of Syrians reminds him of the recent war with Israel and the shelling of Gaza. "What hurts is that we've seen the war in Syria going on for four years and we can't see any end to it. It would move anyone, wherever they are, to want to speak out."

Half of the nearly 5,000 tweets posted with the tag are from Lebanon, where it's mainly been used by young people from across the religious spectrum. One of those pushing the tag, Reem Al-Ayoubi, told Trending that images of child victims first motivated her and others in her network. "The hashtag is aimed at the Syrian regime and its backers," she says.

Several Lebanese also used the tag to criticise Hezbollah, the Lebanese Shia militia, and its links to both President Assad and Iran. BBC Monitoring's Sara Fayyad says many feel that Hezbollah leader Hassan Nasrallah wants to drag Lebanon into the conflict, especially with its recent involvement in a battle on the Lebanese border.

But the slogan also spread to Gulf countries. One of those with the biggest online following who used it was Hakim Al-Mutairi, the Kuwaiti leader of the Islamist organisation Ummah Conference (also known as the Ummah Party), who has backed some of the Islamists fighting President al-Assad. His tweet showed a picture of a dead child and was retweeted more than 300 times.

Blog by Sumaya Bakhsh

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