Members of two Al-Qaeda-affiliated rebel groups have clashed in Syria's northeastern Hasakeh province, with one group seizing the local headquarters of the other, a Syrian NGO said on Sunday.
Fighters from the Islamic State of Iraq and the Levant (ISIS), an Iraqi Al-Qaeda branch that has expanded into Syria, attacked the headquarters of Al-Nusra Front in Shadadi, the Syrian Observatory for Human Rights said.
"ISIS fighters on Saturday attacked the Nusra Front regional headquarters in Shadadi, taking control of the headquarters and seizing weapons and oil production equipment," the group said.
The two sides clashed, but the Observatory said Al-Nusra had relatively few fighters at the headquarters because they are currently battling Kurdish forces elsewhere in the region.
Al-Nusra Front has pledged allegiance to Al-Qaeda chief Ayman al-Zawahiri, but its leader rejected an ISIS merger bid.
The two groups have fought alongside each other, however, and it was unclear whether the clashes were caused by a local dispute or a sign of broader tensions.
Elsewhere, ISIS fighters have clashed with members of more moderate brigades belonging to the Free Syrian Army.
ISIS and Al-Nusra share a similar ideology, and some of the latter's fighters joined ISIS when it expanded into Syria.
Elsewhere, an ISIS fighter blew himself up in a car bomb that targeted a police post outside the capital Damascus, the Observatory said.
The attack, on the main road between Damascus and Homs, wounded several people but only the bomber was reported killed, the Observatory said.
State news agency SANA said the bomber was killed by army gunfire and that the car exploded before reaching its target.
Nearby, state media said Syrian troops had advanced in the northern Damascus district of Barzeh, where the army has been battling rebels for months.
The Observatory reported at least two regime air raids on the neighborhood, but there was no immediate information on casualties.