Gunmen 'kill seven' at Syrian pro-Assad Ikhbariya TV
Gunmen have attacked a Syrian pro-government TV channel, killing seven people, state media say.
Journalists and security guards died in the attack on al-Ikhbariya TV south of Damascus, Sana news agency reported.
Hours earlier, President Bashar al-Assad said Syria was in "a real state of war" and US intelligence officials predicted a long, drawn-out struggle.
UN and Arab League envoy Kofi Annan has called a meeting of the UN action group for Syria for Saturday.
His deputy envoy said on Wednesday that the violence in the country had "reached or surpassed" levels before the April ceasefire deal.
The BBC's Jim Muir in Beirut says that Syrian TV dropped normal programming on Wednesday to run live coverage of the attack on the headquarters of Ikhbariya TV in the town of Drusha, some 20km (14 miles) south of the capital.
State TV showed pictures of burnt and wrecked buildings, with fires still smouldering.
Syria's Information Minister Omran al-Zoebi, on a visit to the site, said some of the victims had been abducted, bound, and killed in cold blood.
He also condemned the EU's decision to impose sanctions on Syria's state-run TV and radio agency for its support of the Assad government.
The Ikhbariya attack followed fierce clashes in suburbs of the capital, Damascus, described by opposition activists as the worst there so far.
The UK-based Syrian Observatory for Human Rights said fighting had taken place near positions of the Republican Guard, which is led by President Assad's younger brother Maher and has the role of protecting the capital.
The Observatory also reported violence on Wednesday in the central city of Homs, Deir al-Zour in the east and in Idlib in the north.
Mr Annan has announced there will be a meeting in Geneva on Saturday of the Syrian action group - the five permanent members of the UN Security Council plus Turkey, Iraq, Kuwait and Qatar.
There was no mention of including Iran, whose presence in talks has been urged by Russia.
Mr Annan said the aim of the meeting was to secure full implementation of an agreed peace plan and back the "principles for a Syrian-led political transition".
US Secretary of State Hillary Clinton, who will attend the meeting, said that if all the parties agreed to Mr Annan's roadmap for political transition then there was "great hope that this perhaps can be a turning point in the very tragic circumstances affecting the Syrian people".
In April, following months of bloodshed, the Syrian government agreed to a six-point peace plan. UN monitors were deployed to oversee a ceasefire but the truce never took hold and the monitors have suspended patrols.
Mr Annan's deputy envoy, Jean-Marie Guehenno, warned the UN Human Rights Council in Geneva on Wednesday that "time was running out".
He was speaking shortly before a commission of inquiry gave details of its report on the one of the worst attacks on civilians since the conflict began - the 25 May Houla massacre in which 108 people died.
Commission chairman Paulo Pinheiro told the council that "forces loyal to the government may have been responsible for many of the deaths" but he said his team had been unable to determine who was behind the massacre.
Mr Pinheiro said the perpetrators were from one of three groups: "shabiha" or other local militia from neighbouring villages, perhaps acting with the army; anti-government armoured groups; or foreign groups.
"While the commission could not rule out the possibility of anti-government fighters being responsible for the killing, this was considered very much unlikely," he said.
Syrian ambassador Faisal Khabbaz Hamoui condemned the meeting as "flagrantly political" and walked out of the hall.
Senior US intelligence officials have described the conflict between the Free Syrian Army (FSA) and the government as a "seesaw battle", suggesting that it is likely to be a long, drawn-out struggle.
"The regime inner circle and those at the next level still seem to be holding fairly firm in support of the regime and Assad," one official told Reuters.
The BBC's Ian Pannell, who has spent the past two weeks with rebel groups in Idlib province, says that over the past two months there have been marked changes, with the rebels clearly getting weapons across the border and from the Syrian military.
The rebels are becoming more organised and are going on the offensive, he says, and are controlling large swathes of northern areas.
The UN says at least 10,000 people have been killed since pro-democracy protests began in March 2011. In June, the Syrian government reported that 6,947 Syrians had died, including at least 3,211 civilians and 2,566 security forces personnel.