Syrian forces backed by tanks have killed at least 14 civilians in the city of Homs in one of the fiercest military assaults on urban centres to crush six months of pro-democracy protests, activists and residents said.
The Obama administration has frozen the US assets of Syria's foreign minister and two other senior officials in response to Syria's increasingly violent crackdown against anti-government protesters.
Iran has warned NATO against any temptation to intervene in Syria, saying that rather than the defeating a regime it would be bogged down in a "quagmire" similar to Iraq or Afghanistan.
In a choreographed diplomatic squeeze play, President Barack Obama, the leaders of Britain, France and Germany and the European Union have joined to demand that Syrian President Bashar Assad resign, saying his brutal suppression of his people had made him unfit to lead.
More than 5000 Palestinian refugees have fled a camp in the besieged Syrian city of Latakia after President Bashar Assad's forces shelled the city during a broad military assault to root out dissent, the UN says.
Syrian gunboats firing heavy machine guns have pounded impoverished districts of Latakia, killing at least 10 people in a renewed assault on the Mediterranean coastal city, activists said.
Despite five months of blistering attacks on dissent, the Syrian regime has yet to score a decisive victory against a pro-democracy uprising determined to bring down the country's brutal dictatorship.
Two Syrian rights groups say government forces have killed at least 31 people in the latest phase of their crackdown on dissent and the toll for the day could rise to 69.
The flashpoint Syrian city of Hama has endured a fifth day under military siege, with a resident saying people were being "slaughtered like sheep" in the streets and families were burying their dead in home gardens or roadsides rather than risk a trip to a cemetery.
The UN Security Council has condemned Syrian authorities for attacking civilians and committing widespread human rights violations.
Syrian tanks and the government's most loyal troops pushed into more towns and villages, trying to snuff out any chance that the uprising against President Bashar Assad could gain a base for a wider armed rebellion.
Syrian policemen turned their guns on each other, soldiers shed their uniforms rather than obey orders to fire on protesters, and three young men who tried to escape were beheaded by forces loyal to President Bashar Assad.
Syrian President Bashar Assad claimed the country's "crisis" is drawing to a close even as forces unleashed tank shells on opponents and US sanctions took aim at the Syrian leader and his senior aides for their brutal crackdowns.
Mobilised by calls on Facebook, thousands of Arab protesters marched on Israel's borders with Syria, Lebanon and Gaza in an unprecedented wave of demonstrations, sparking clashes that left at least 15 people dead in an annual Palestinian mourning ritual marking the anniversary of Israel's birth.
Syria has promised to end its military operation in the southern city of Daraa, where its forces are besieging the anti-government protesters that sparked a wave of demonstrations across the authoritarian nation.
The UN Security Council has failed to agree on a statement condemning Syrian violence against peaceful protesters.
European nations summoned Syrian ambassadors in a co-ordinated demand that President Bashar Assad stop gunning down his people, and Germany said sanctions were possible if the crackdown did not ease.
Thousands of soldiers backed by tanks and snipers have moved in to the city where Syria's anti-government uprising began, causing panic in the streets by opening fire indiscriminately on civilians and going house-to-house rounding up suspected protesters.
Thousands of students have held demonstrations against Syria's authoritarian regime, brushing off President Bashar Assad's sweeping declarations of reform as the country's growing protest movement vowed to stage the biggest rallies to date on Friday.