Gunmen fired shots at UN monitors trying to get into a Syrian massacre after the reported massacre of dozens of inhabitants, UN leader Ban Ki-moon said Thursday.
None of the monitors were injured but the UN team had to abandon until Friday attempts to get to Al-Kubeir, a UN spokesman added.
"UN monitors were initially denied access," Ban told a UN General Assembly meeting on the Syria crisis.
"They are working now to get to the scene and I just learned a few minutes ago that while trying to do so, the UN monitors were shot at with small arms."
A UN spokesman, Farhan Haq, later gave more details of the attack.
"The mission reports that, around 3 pm (1300 GMT) local time today, a four-vehicle convoy from the mission was hit by small arms fire in Hama, while en route to investigate yesterday's alleged killings," Haq said.
"No UN military observers were injured, but one vehicle was slightly damaged. The patrol was forced to withdraw to a nearby government checkpoint."
Al-Kubeir is close to the protest city of Hama.
"The monitors were not able to enter Al-Kubeir today. They will try again tomorrow," Haq added.
Ban again strongly condemned President Bashar al-Assad's government over the recent massacres in Houla and Al-Kubeir.
"The trail of blood leads back to those responsible," he said. "Any regime or leader that tolerates such killing of innocents has lost its fundamental humanity."
Ban called the reports coming from Al-Kubeir "shocking and sickening."
"We condemn this unspeakable barbarity and renew our determination to bring those responsible to account," he said.