At least 25 people have died in an attack by Syrian fighter jets on the Palestinian Yarmouk camp in Damascus, opposition activists say. Chief Correspondent Alex Thomson is in Syria.

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The rocket attack on Yarmouk reportedly hit people sheltering in a mosque, killing at least 25.

The camp on the southern fringes of Damascus houses both Palestinian and Syrian refugees, displaced by fighting in other areas of the country.

Channel 4 News Chief Correspondent Alex Thomson, who is in Syria, said the attack was a "significant escalation of the war in the capital."

Fighting has intensified in Damascus in recent weeks, with particularly fierce battles over the airport.

The attack on Yarmouk is the first reported aerial attack of this scale on the camp since the popular uprising against Syrian President Bashar al-Assad erupted 21 months ago and evolved, after he tried to suppress protests using force, from peaceful protests into full-blown civil war.

Around 40,000 Syrians have died in the fighting and food shortages are beginning to take hold in parts of the country as clashes continue in various locations.

The Syrian deputy foreign minister Faisal Mekdad told Channel 4 News that the government is not targeting civilians but the international community is not convinced.

This evening in Paris, French Foreign Minister Laurent Fabius said he believed the Syrian ruler would fall soon.

"I think the end is nearing for Bashar al-Assad," Fabius told RFI radio, describing the attack on Yarmouk as scandalous.

"You have to ask yourself whether President Assad is not trying to enflame the region (through it)," the minister said.

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