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 yesterday authorised cross-border military operations after a Syrian shell killed five civilians on Turkish territory the day before.
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 today'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 today. "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.
Homs is Syria's third largest city. Regime forces pounded parts of Homs for months, leaving large swaths of the city in ruins by April. Since then the level of violence has dropped, although gun battles still frequently break out.
The uprising against Assad erupted in March 2011 and gradually morphed into a bloody civil war, killing more than 30,000 people, according to activists.
The Observatory also said the Syrian military has been shelling the neighbourhood of Sakhour in Aleppo as government forces battle rebels in the country's largest city.
State-run Syrian TV said that government forces "cleansed Sakhour of terrorists and mercenaries".
Syria's government has always blamed the uprising on what it calls foreign terrorists, despite months of peaceful protests that turned violent after repeated attacks by security forces. The transformation of the conflict into an open war has given an opportunity to foreign fighters and extremists, analysts say.
Turkey today deployed troops along the border with Syria, the day after the Turkish parliament approved a bill that authorises the military to conduct operations outside the Turkish border, including Syria.
An Associated Press reporter saw Turkish soldiers patrolling the area on foot and in armoured personnel vehicles.
People in the border town of Akcakale, where the Syrian shell landed on Wednesday, feared more violence in the volatile border area.
Halil Deniz, who lives in Oncul, said he still fears for his life. Oncul is a village on the Turkey-Syria border to which people fled from Akcakale, where five civilians died when a Syrian shell hit it.
"We do not know if we will live or die," Mr Deniz said. "Children go to other villages in the evenings, and return back when the next day dawns."
"Our store owners, our citizens and our children are all very concerned. We did not sleep until morning," said Ahmet Sabritur, who resides in Akcakale. He praised Turkey's military response to the Syrian shelling, saying that Damascus should be made aware that deaths of Turkish civilians will not go unpunished.
"If our government had not retaliated, maybe it could have been worse," Mr Sabritur said. "They (the Syrians) could have attacked this town a second time."
Turkey's planes pounded targets inside Syria for two days in retaliation for the killings. Although both Damascus and Ankara moved yesterday to calm tensions, the parliament's approval of the cross-border operations made it clear that Turkey is retaining a military option if threatened.