Syrian warplanes and artillery have pounded the central city of Homs, subjecting the former rebel stronghold to its worst bombardment in months, activists said.
The reported bombardment by tanks and mortars as well as aircraft comes alongside a push by government forces on another front, the embattled northern city of Aleppo.
The stepped-up pace of government attacks on Syrian cities suggests that the Damascus regime's forces have not been distracted by escalating tensions with its northern neighbour, Turkey. Ankara's parliament on Thursday authorised cross-border military operations after a Syrian shell killed five civilians on Turkish territory the day before.
Turkey on Friday deployed troops along the border with Syria. An Associated Press reporter saw Turkish soldiers patrolling the area on foot and in armoured personnel vehicles.
Homs has been one of the flashpoints of the 18-month-old uprising against president Bashar Assad's regime. The focus of fighting has shifted to other areas in recent months, including Aleppo, since a government offensive against rebel strongholds in Homs ended in April.
The Britain-based Syrian Observatory for Human Rights said Friday's attack is the worst the city has seen in five months. The Observatory, which relies on a network of activists on the ground, said tanks and mortars as well as aircraft had bombarded the city's Khaldiya neighbourhood.
"Around dawn, the regime went crazy and started shelling hysterically," a Homs-based activist known as Abu Rami told the Associated Press. "An average of five rockets a minute are falling." Abu Rami was speaking from the central rebel-held old quarter known as Old Homs.
He said the government forces are mainly firing rockets and heavy mortars at the rebel-held neighbourhoods of Old Homs, Khaldiya, Qusour and Jouret el-Shayah. Abu Rami also said the regime forces have been shelling villages around Homs and the rebel-held town of Rastan, just north of the city.
He said there were no immediate reports of casualties, adding that most residents who still live in rebel-held areas around the city are hiding in shelters.
Activists say most government forces near Homs are stationed outside the town - a common pattern in rebel strongholds.