Syria army seizes Jdaidet al-Fadl 'killing dozens'
Syrian government troops have seized a town near Damascus, killing at least 80 people including women and children, opposition activists say.
The army stormed the town of Jdaidet al-Fadl after five days of heavy fighting, they report.
Syria's Sana state news agency said government forces had "inflicted heavy losses upon terrorists" in the town.
At least 70,000 people have died since the uprising against President Bashar al-Assad began in March 2011.
The latest killings come as the army tries to break a ring of rebel-held areas around Damascus.
UK Foreign Secretary William Hague said he was appalled by the reports: "This is yet another reminder of the callous brutality of the Assad regime and the terrible climate of impunity inside Syria.
"It underlines the urgent need to bring the conflict in Syria to an end. At the Friends of Syria Core Group meeting with the Syrian opposition National Coalition in Istanbul, we agreed to redouble efforts to reach a political resolution and increase support to the opposition, and I will be discussing these efforts with European foreign ministers today."
The Syrian Observatory for Human Rights (SOHR), a UK-based activist group, said it was able to identify at least 80 people killed in Jdaidet al-Fadl, to the south-west of the capital.
The SOHR - which has also released footage of the bloodshed - said some of the victims were summarily killed. There were reports of as many as 250 deaths, it added.
The organisation documents and reports incidents and casualties in the Syrian conflict and says its reports are impartial, though its information cannot be verified.
Meanwhile, Reuters news agency quoted an activist in a nearby area as saying that 85 people had been summarily killed in the town.
Abu Ahmad al-Rabi said this included "28 shot at a makeshift hospital after Assad's forces went in Jdaidet al-Fadl".
"We fear that the victims of the massacre are much higher," the activist added.
The Sana news agency confirmed the fighting had taken place in Jdaidet al-Fadl.
It said that a number of "terrorists" were killed and injured, without providing further details.
On Saturday, US Secretary of State John Kerry announced a doubling of US aid to Syria's rebels to $123m (£81m), including new, non-lethal military equipment.
Speaking at a meeting of the Friends of Syria group in Istanbul, Mr Kerry described the situation in Syria as "horrific".
The rebels have been pushing for military supplies and insisted that any weapons they received would not "fall into the wrong hands".
The US and EU have so far refused to supply the rebels with weapons, amid concerns that they may end up in the hands of Islamist extremists inspired by al-Qaeda.
Before the Istanbul talks, the main opposition expressed its frustration with the lack of support, urging allies to act more decisively.