Syrian rebels in the central Homs province have taken over parts of an important arms depot, seizing a large quantity of weapons, a monitoring group said Wednesday.
A Syrian security official in Damascus, speaking to AFP on condition of anonymity, denied rebels had advanced or seized weapons, but said the fighting was still under way.
The conflicting reports come just over two weeks after jihadists and other rebels launched a major offensive aimed at capturing one of Syria's largest weapons depots, near Mahin in the Homs countryside.
The Syrian Observatory for Human Rights -- a Britain-based group which relies on activists and other sources inside Syria -- said more than 50 rebel fighters and 20 loyalists were killed in Tuesday's battle.
Fighters from Al-Nusra Front and the Islamic State of Iraq and the Levant (ISIL) -- both linked to Al-Qaeda -- and the Al-Khadraa and Baba Amr Commandos battalions "took over buildings of an army weapons depot near Mahin," the Observatory said.
The rebels "seized a large amount of weapons" in the complex, which comprises some 30 buildings, it added.
The Syrian security official denied the report, saying: "The battle is continuing, the terrorists did not take any weapons, and there are many losses in their ranks."
The Syrian regime refers to all the rebels battling to overthrow President Bashar al-Assad as "terrorists."
The advance comes weeks after mainstream rebels and jihadists captured a major army position dubbed Base 66, in the east of Hama province, where they also seized a large amount of heavy weapons.
In Damascus, meanwhile, a mortar round fell near the central Umayyad Square, according to the Observatory, which in recent weeks has reported frequent rebel shelling on areas of the city that are under government control.
In the north, fighting raged near a power plant just outside the city of Aleppo, pitting loyalists against jihadists and other rebels.
The Observatory said there were "fears the fighting might cause explosions in the plant," possibly leading to "a total blackout in Aleppo city."
Much of Aleppo has been destroyed by army bombardment and fighting ever since a massive rebel advance on the city in July 2012.
More than 120,000 people have been killed in Syria's 31-month war, and millions more forced to flee their homes.
The civil war began after Assad launched a brutal crackdown on peaceful protests inspired by the 2011 Arab Spring.