Syria on Sunday, July 15 denied UN claims that government forces used heavy weapons during a military operation that left scores dead and brought immediate international condemnation, while the International Committee of the Red Cross said it now considers the conflict in the country a civil war, the Associated Press reports.

Syrian Foreign Ministry spokesman Jihad Makdissi said the violence Thursday was not a massacre - as activists and many foreign leaders have asserted - but a military operation targeting armed fighters who had taken control of the village of Tremseh.

"What happened wasn't an attack on civilians," Makdissi told reporters in Damascus. He said 37 gunmen and two civilians were killed - a far lower death toll than the one put forward by anti-regime activists, some of whom estimate that more than 100 people were killed.

"What has been said about the use of heavy weapons is baseless," Makdissi added.

But the United Nations has already implicated Assad's forces in the assault. The head of the UN observer mission said Friday that monitors stationed near Tremseh saw the army using heavy weaponry and attack helicopters.

ICRC spokesman Hicham Hassan said Sunday that humanitarian law now applies wherever hostilities are taking place in Syria, where fighting has spread beyond the hotspots of Idlib, Homs and Hama. International humanitarian law grants parties to a conflict the right to use appropriate force to achieve their aims. But attacks on civilians and abuse or killing of detainees can constitute war crimes.