Unarmed UN monitors attempting to reach the site of a massacre in Hama were shot at “with small arms” by pro-Assad forces, Secretary General Ban Ki-Moon said at the UN General Assembly on Thursday.

Ban condemned the reported killing of 78 people, including 40 women and children, in the Mazraat al-Qubeir village in central Syria on Wednesday.

“Today’s news reports of another massacre … are shocking and sickening,” he told the assembly. “A village apparently surrounded by Syrian forces. The bodies of innocent civilians lying where they were, shot. Some allegedly burned or slashed with knives.”

Syrian state television denied the UN claim that observers were banned from visiting the site, and said they arrived safely to the village.

Ban called on President Bashar Assad to implement UN mediator Kofi Annan’s six-point peace plan.

“We place full responsibility at the feet of the Assad regime,” said US envoy to the UN Rosemary DiCarlo.

“To date the Assad regime has made no serious efforts to adhere to the Annan plan,” she said.

Arab League Secretary General Nabil Elaraby called for Arab countries to sever ties with the Assad regime at the UN meeting on Thursday.

The reported Hama massacre follows the massacre near the town of Houla on the night between May 25 and 26, in which more than 100 people, many of whom children, were killed and emptied into mass graves.

By contrast, Iranian UN envoy Mohaammad Khazaee called for an end to foreign financing and arming of opposition groups in Syria and urged international restraint in blaming Assad. He said that hurling accusations only further inflames the crisis.