A battle on the outskirts of the northern city of Raqa, near the Turkish border, killed 26 oppostion fighters on Saturday, a watchdog reported.
“Fierce clashes pitting rebel fighters from several battalions against regular troops have raged since dawn on the outskirts of Raqa city,” AFP news agency reported, citing the Syrian Observatory for Human Rights.
“Army troops shelled several city neighborhoods, as well as the outskirts, while the clashes left dozens of troops and rebels dead,” the Britain-based group said without giving exact numbers.
“Explosions could be heard in the city, and towers of smoke could be seen rising into the sky.”
Both the Observatory and activists in Raqa said the army was using helicopters to strafe rebels in some parts of the city, in a rare escalation of violence in the provincial capital.
Raqa city is strategically located near Syria’s northern border with Turkey. Residents say it has become home to thousands of people forced to flee their homes in other war-torn parts of Syria.
Syrian troops retook on Friday a checkpoint on the northeastern border with Syria, captured a day earlier by Jihadist fighters of al-Nusra Front, the Syrian Observatory for Human Rights said on Friday.
The rebels had overrun the post at Yaarubiyeh in oil-rich Hassakeh province on Thursday after fierce clashes, the Britain-based Observatory said.
“Government forces succeeded in retaking the Yaarubiyeh crossing less than 24 hours after it was taken by fighters from the Al-Nusra Front” and other rebel elements, the Observatory said.
They also “captured half of the city of Yaarubiyeh,” it added.
Four wounded Syrian regime soldiers are being treated at a north Iraq hospital after clashes with rebels on the Syrian side of the border, the Iraqi defence ministry's spokesman said on Saturday.
"Four wounded Syrian soldiers were moved to Rabia Hospital, which is close to the Yaarubiyeh border crossing" from Syria into Iraq's Nineveh province, Mohammed al-Askari told AFP by telephone.
Al-Nusra Front, an increasingly influential factor in Syria’s conflict, also took control of the nearby town of Shaddadeh and surrounding villages in mid-February.
The border crossing was controlled by rebel forces last year before the army recaptured it.
Al-Nusra Front first gained notoriety for its suicide bombings in Syria’s main cities and has evolved into a strong fighting force leading attacks on battlefronts throughout the country.
Its tactics and suspected affiliation to al-Qaeda’s offshoot in Iraq have landed it on the U.S. list of terrorist organizations.
Rebels of the mainstream Free Syrian Army have (FSA) told AFP news agency that al-Nusra fighters, despite their small numbers, have greater economic and logistical support than other insurgents and funding from abroad.
The jihadist group targets strategic points mainly in eastern Syria, including oil and gas facilities, and draws recruits from the local population by paying them a salary.
It aspires to create an Islamic state in Syria, whose regime accuses Saudi Arabia and Qatar of financing Islamist fighters in the two-year-old conflict that the U.N. says has killed at least 70,000 people.
On Friday, Iraqi forces opened fire on Syria shelling the positions of the FSA days after Iraqi Prime Minister Nouri al-Maliki warned that a victory of the Syrian opposition would spread chaos in the region.
An Al Arabiya correspondent near the Syrian-Iraqi border reported that Iraqi snipers took up positions on buildings near the Rebiya crossing while others forces shelled the positions of the Free Syrian Army.
The correspondent said that large reinforcements were being deployed by the Maliki government in Baghdad near the Syrian borders.
On Wednesday, Maliki warned if victory by Syrian rebels will spark sectarian wars in his own country and in Lebanon and will create a new haven for al-Qaeda that would destabilize the region.
“Neither the opposition nor the regime can finish each other off,” he said. “If the opposition is victorious, there will be a civil war in Lebanon, divisions in Jordan and a sectarian war in Iraq,” Maliki said in an interview with the Associated Press.