Damascus denied using cluster bombs to combat rebel forces, as new videos showed cluster bomb canisters and widely ejected small "bomblets" in Syrian cities.
Syria's army "does not possess these kinds of weapons" and the allegations are therefore "baseless," the armed forces general command said in a statement carried over state television.
It said such cluster-bomb reports "are untrue and come in the framework of misleading media that are aimed at diverting public opinion from the practices of the armed terrorist groups against civilians."
"Armed terrorist groups" is the regime's term for insurgents seeking President Bashar Assad's ouster.
The regime accused "some news outlets" of being "complicit in the bloodletting in Syria."
The non-governmental organization Human Rights Watch said Sunday Syrian regime forces dropped Russian-made cluster bombs on civilian areas last week in an effort to reverse rebel gains on a strategic highway between Damascus and Aleppo.
The rights group said the use of the bombs, which eject many deadly explosive bomblets, could constitute a war crime.
"Syria's disregard for its civilian population is all too evident in its air campaign, which now apparently includes dropping these deadly cluster bombs into populated areas," said Human Rights Watch Arms Director Steve Goose.
The group reported in July and August that Syria used cluster bombs.
Russian Foreign Minister Sergei Lavrov said the HRW report had not been confirmed, but if it was true, the bombs could have been made by other former Warsaw Pact countries.
"The region is full of weapons. Weapons are being sent to Syria and other countries of the region in huge quantities and illegally," Lavrov told Russian journalists in Luxembourg.
"It's very hard to establish who is supplying ammunition and other types of weaponry and from where," he said.
Eliot Higgins, a British blogger whose Brown Moses blog is widely considered an authoritative source on arms used in the Syrian conflict, reported new video evidence Monday the Syrian air force had dropped cluster bombs.
"Here's the latest videos of cluster bombs and bomblets from the last 24 hours in Syria, starting with two videos from Al-Bab [district], [in] Aleppo [province], showing [Russian] PTAB 2.5m bomblets, as well as the canister in the second video," the blog said.
Other videos and still photos showed bombs and parts of bombs in and around Damascus, Deir Ezzor, Homs and Idlib.
Higgins' videos were cited by Human Rights Watch in its Sunday report.
Syria, along with a number of other countries including the United States and Israel, has not signed a 2008 international agreement that bans such weapons.
Seventy-six other countries signed the Convention on Cluster Munitions and have outlawed cluster bombs, which kill and damage indiscriminately.
Reports of fighting in Syria Monday came mostly from Aleppo, Syria's largest city, where the landmark 13th century Great Mosque, also known as the Ummayad Mosque, was severely damaged by rebel-fired rocket-propelled grenades, witnesses said.
The official Syrian Arab News Agency said Assad had ordered the UNESCO World Heritage site repaired.
The mosque is said to entomb the remains of the biblical Zechariah, father of Christianity's John the Baptist.
One hundred people, including seven children and 3 women, were killed in Syria Monday, the activist Local Coordination Committees reported. The dead included 34 people in Damascus and its suburbs and 29 in Aleppo.