There has been further heavy fighting in the Syrian capital, Damascus, and the northern city of Aleppo.
Activists said government forces were closing in on Hajar al-Aswad, a southern suburb of Damascus, and the situation for residents was desperate.
State media said troops had killed many of what they called “terrorists”.
Earlier, Amnesty International warned that indiscriminate air and artillery strikes were causing a dramatic rise in civilian casualties in Idlib and Hama.
The report said the plight of people in the two provinces had been under-reported because world attention had focused on Damascus and Aleppo.
Meanwhile, Iranian Foreign Minister Ali Akbar Salehi has arrived in Damascus to meet President Bashar al-Assad and other officials.
Mr Salehi had earlier called for a halt of violence by both sides and insisted on a peaceful solution without foreign intervention in Syria.
A Syrian general who defected to the opposition told the Times newspaper that the president had discussed the possibility of using chemical weapons in the conflict, and even whether they should be transferred to the Lebanese Shia Islamist movement, Hezbollah.
“We discussed this as a last resort – such as if the regime lost control of an important area such as Aleppo,” Gen Adnan Sillu said.
Advance
On Wednesday, opposition activists said the military was attacking the south-western Damascus suburbs of Muadhamiya, Jadidat Artouz, Kanakir, the north-western districts of Qadam and Assali, and the southern district of Hajar al-Aswad.
They said the situation in Hajar al-Aswad was desperate, with areas being bombarded by aircraft and heavy weapons as troops advanced.
They posted video footage online which they said showed helicopter gunships firing rockets, also the bodies of some of the more than 20 people they said had been killed.
State media said troops had moved into Hajar al-Aswad and clashed with an “armed terrorist group” near a local cemetery, eliminating “a number of its members”.
In Aleppo, activists said government forces had bombarded several central areas surrounding the Old City, including Bab al-Hadid, Bab al-Nasr, and also attacked the outlying districts of Hananu and al-Bab.
Activists also reported that the towns of Marea and Anadan, north of Aleppo, and al-Muhassin, near Deir al-Zour, had come under fire.
The Local Co-ordination Committees, an activist network, said more than 160 people were killed across the country on Tuesday, including 67 in Damascus and its suburbs, where the majority died as a result of shelling.
Unguided bombs
The reports of violence came as Amnesty International said indiscriminate air attacks and artillery strikes by Syrian government forces are killing, maiming, and terrorising civilians in in the Idlib, Jabal al-Zawiya and north Hama regions.
Donatella Rovera, Amnesty’s senior crisis response adviser, who recently returned from northern Syria, told the BBC that there was evidence that the army and air force were increasingly using battlefield weapons in residential areas where government troops had been forced out by opposition forces, with disastrous consequences for civilians.
“They are using in equal measure air-delivered, large, old, Soviet-era unguided bombs – free-fall bombs – the opposite of smart bombs,” she said. “They are dropped over an area. There’s no way you can target them at a specific target or specific building.”
“They fall over people’s houses, over markets, in the street. Many of those who were killed and injured are children. Every day, in the field hospitals, on the ground, in the streets and in people’s homes I was seeing the disastrous consequences of these attacks on civilians.”
Amnesty’s report says the group carried out first-hand field investigations in the first half of September into attacks which killed 166 civilians, including 48 children and 20 women, in 26 towns and villages.
It says the plight of civilians in Hama and Idlib has been under-reported because world attention has largely focused on the fighting in Aleppo and Damascus, and that such indiscriminate attacks constitute war crimes.
BBC
