United Nations monitors have said Syrian helicopters fired on rebel strongholds north of Homs and that many women and children are trapped in the city.
The observers called on Monday for “immediate and unfettered access” to the conflict zones, while in Haffeh, a mainly Sunni town near the Mediterranean coast, the US State Department said it feared a “potential massacre”.
It was the first time the UN has verified repeated allegations by activists that Assad’s forces have fired from helicopters in the military crackdown on rebels.
“UN observers reported heavy fighting in Rastan and Talbiseh, north of [Homs], with artillery and mortar shelling, as well as firing from helicopters, machine guns and smaller arms,” UN spokeswoman Sausan Ghosheh said in a statement.
International envoy Kofi Annan said he is “gravely concerned” about the latest violence in Syria. In a statement on Monday, Annan said there was an escalation of fighting by government and opposition forces.
Violence has spiked in recent weeks, with both sides ignoring a UN-brokered cease-fire that was supposed to go into effect on April 12, but never took hold.