Syria's rebels on Monday seized the strategic town of Khan al-Assal, a regime bastion situated in the northern province of Aleppo, a monitoring group said.
Khan al-Assal was the last regime bastion in the west of Aleppo province, which lies on the Turkish border, said the Syrian Observatory for Human Rights.
Large swathes of northern and eastern Syria are in rebel control, while much of central and southern Syria is squarely in regime hands.
"Opposition fighters have taken control of the town of Khan al-Assal, which is strategically located in the west of Aleppo province," said the Observatory.
The rebel Ninth Division also announced it had captured Khan al-Assal in an online video.
"We the leadership of the Ninth Division announce that the town of Khan al-Assal has been completely liberated," a rebel commander said in a video posted on Youtube.
The Ninth Division is also fighting in western Aleppo city, where rebels launched in June a bid to take over areas still under regime control.
The Britain-based Observatory, meanwhile, reported continued clashes on the southern outskirts of Khan al-Assal.
The rebels had tried for several months to advance on Khan al-Assal.
The town's biggest battle took place in March, when the rebels took control of the police academy there, and temporarily seized several other positions.
The rebels lost some 200 men in an eight-day battle at the time.
On March 19, the regime and the opposition exchanged blame for a chemical weapon attack in Khan al-Assal that killed some 30 people, according to Observatory, regime and other tolls released at the time.
On Wednesday, the United Nations accepted a Syrian government invitation for a visit by two senior UN officials for talks on the alleged use of chemical weapons in the country's 28-month war.
Monday's violence comes a day after at least 232 people were killed across Syria, said the Observatory, adding that the toll was one of the highest in recent months.
It was particularly high in Damascus province, where 49 rebels were killed in an army ambush and a battle that ensued in the strategic town of Adra, the group added.
Some 100,000 people have been killed in Syria's war since the uprising against President Bashar al-Assad erupted in March 2011, according to Observatory figures.