The UK-based Syrian Observatory for Human Rights has urged the UN Security Council to act urgently after regime forces 'massacred' over 90 people, including many children, in the Syrian town of Houla.

Opposition activists said on Friday that Syrian forces shelled the town of Houla, a cluster of villages north of the city of Homs, after skirmishing with insurgents.

The shelling had killed more than 90 people in Houla, including 25 children, said media report quoting Syrian oppostion activists.

Amateur videos posted on YouTube showed horrifying images of children lying dead on a floor. Some of their corpses badly mangled, including at least one child whose head had been partly blown away.

According to Opposition, the residents continued to flee the town, in central Homs province, in fear that artillery fire would resume.

The Syrian Observatory for Human Rights meanwhile accused the Arab and international communities on Saturday of being 'complicit' in the killing, saying shelling that had begun on Friday had continued into the night.

The Observatory said the international community stood 'silent in the face of the massacres committed by the Syrian regime.'

The latest flare-up of violence came as Kofi Annan, the UN-Arab League envoy to Syria who brokered a repeatedly violated ceasefire last month, finalised plans to return to Damascus

Earlier on Saturday, SNC spokeswoman Basma Kodmani said 'more than 110 people were killed (half of whom are children) by the Syrian regime's forces' in Houla. 'Some of the victims were hit by heavy artillery while others, entire families, were massacred.'

A report by UN Secretary General Ban Ki-moon said groups fighting President Bashar al-Assad now control 'significant' parts of some cities and there is 'considerable physical destruction' across the country.

'There is a continuing crisis on the ground, characterised by regular violence, deteriorating humanitarian conditions, human rights violations and continued political confrontation,' said the report, which will be debated by the Security Council next week.