Syrian opposition fighters have clashed with armed Kurds near the Turkish border, the latest sign of an emerging power struggle in Syria's ethnically diverse northeast.
Gunfire erupted on Monday in the mixed Arab and Kurdish frontier town of Ras al-Ain, which was overrun by the mainly Sunni Muslim Arab rebels on November 8 and bombed by Assad's forces in the days that followed.
Fleeing residents said the fighting was between the opposition Free Syrian Army (FSA) and Kurds affiliated with the Democratic Union Party (PYD), a Syrian Kurdish party with links to Kurdish separatist fighters in Turkey.
The UK-based Syrian Observatory for Human Rights said at least four Kurdish fighters were wounded in the fighting and that a rebel sniper had shot dead the leader of Ras al-Ain's local Kurdish Council, Abed Khalil.
"The injuries were the result of clashes between the two sides when rebels launched an assault on a checkpoint belonging to the Units for the Protection of the Kurdish People," it said, referring to a PYD-affiliated group.
Some residents said Kurdish fighters had attacked a house where FSA fighters were staying, and that there had been protests against the fighters in pro-PYD areas of Ras al-Ain.
The accounts could not be independently verified.
In southern Damascus, activists reported heavy clashes between rebels and government forces in the neighbourhoods of Assali and Hajar al-Aswad, while shelling was reported on the Palestinian refugee camp of Yarmouk and in the suburb of eastern Ghouta.
In-depth coverage of escalating violence across Syria
Meanwhile, Syrian state news agency said that government forces clashed with “terrorists” in the suburbs of Damascus and in the southern city of Deir Az-zor.
The violence across the country comes as Germany said it expected Turkey to formally request that NATO missiles be placed on its border with Syria soon, but stepped back from an earlier statement that the move was expected on Monday.
"The most important thing is not whether an official request comes today or in the coming days," Thomas de Maiziere, German defence minister, said on the sidelines of a meeting of European Union defence ministers in Brussels.
Arriving at the meeting earlier, he had said he expected Turkey to formally ask NATO for Patriot surface-to-air missiles on Monday
EU ministers were examining a French call for the 27-bloc to formally recognise the opposition National Coalition as the sole representative of the Syrian people as well as a controversial proposal from Paris to arm the rebels.
On Monday, Italy joined France as the second Western country to recognise the coalition formed at talks in Qatar on November 11 after 20 months of conflict that activists say has killed more than 39,000 people.
"We have recognised the coalition that brings together the various opposition groups as legitimate representatives of the Syrian people," Mario Monti, Italian prime minister, said in Doha.
Britain is expected to fine-tune its position on Tuesday.