By Michelle Nichols
UNITED NATIONS (Reuters) - U.N. observers in Syria described an attack on a village in the Hama region - where about 220 people were reported killed - as "an extension" of a Syrian Arab Air Force (SAAF) operation, the U.N. mission said in an assessment obtained by Reuters on Friday.
"The situation in Hama province continues to be highly volatile and unpredictable," the so-called "flash report" from the U.N. observer mission said. "SAAF forces continue to target populated urban areas north of Hama City in a large scale."
Opposition sources said about 220 people, mostly civilians, were killed in the village of Tremseh when it was bombarded by helicopter gunships and tanks then stormed by militiamen who slaughtered some families on Thursday.
"The operation in Tremseh is assessed as an extension of the SAAF operation in Khan Sheikhoun to Souran over the recent number of days," said the two-page report by the U.N. mission in Syria, known as UNSMIS.
There were no independent accounts of the number of dead or how they were killed. If scores of civilians were killed, this could be the worst atrocity in 16 months of fighting between rebels and the forces of President Bashar al-Assad.
According to the UNSMIS report, a patrol of unarmed U.N. military observers could only get within about 4 miles of Tremseh and were stopped by SAAF commanders because of "military operations."
The patrol observed the situation from a few different locations around Tremseh for about eight hours during which time it heard more than 100 explosions, sporadic small arms and heavy machine gun fire and saw white and black smoke plumes.
It saw an Mi-8 and two Mi-24 helicopters and witnessed one of the Mi-24 helicopters firing air to ground rockets.
"The patrol received several calls from local contacts claiming 50 people had been killed and 150 wounded within Tremseh," the report said.
"Attempts (by the patrol) to contact the local military commander during this period were unsuccessful," it said. "Patrols attempted to access Tremseh via alternate routes without success."
U.N. SECURITY COUNCIL DIVIDED
It said further attempts to get a local ceasefire - so civilians could be evacuated from Tremseh - were made by contacting the Hama Governorate chief of police and the SAAF senior national liaison officer, but did not succeed.
The U.N. observers said they also saw several civilian trucks and cars moving through the area carrying armed men wearing a mix of military and civilian clothing and 10 ambulances, one of which was transporting an armed person.
UNSMIS was deployed to Syria in April to monitor a failed truce as part of international envoy Kofi Annan's peace plan. The U.N. Security Council must decide the future of the mission before July 20, when its initial 90-day mandate expires.
Russia has proposed extending the mission for 90 days, but Britain, the United States, France and Germany countered with a draft resolution to extend the mission for just 45 days and place Annan's peace plan under Chapter 7 of the U.N. Charter.
Chapter 7 allows the council to authorize actions ranging from diplomatic and economic sanctions to military intervention. U.S. officials have said they are talking about sanctions on Syria, not military intervention.
The Western-backed draft resolution in particular threatens the Syrian government with sanctions if it does not stop using heavy weapons and withdraw its troops from towns and cities within 10 days of the adoption of the resolution.
Russian Deputy U.N. Ambassador Alexander Pankin said on Thursday that Moscow was "definitely against" Chapter 7. Russia - a key Syrian ally - and China previously vetoed U.N. resolutions designed to pressure Assad.
The United States and Britain have said the massacre shows it is time for the Security Council to take strong action.
"Reports of (Tremseh) massacre are nightmarish - dramatically illustrate the need for binding UNSC (U.N. Security Council) measures on Syria," U.S. Ambassador to the United Nations Susan Rice tweeted late on Thursday.
(Reporting by Michelle Nichols; Editing by Vicki Allen and Jackie Frank)