\"A man was hiding here. When the soldiers found him, they gunned him down in cold blood,\" said a resident of the Syrian village of Treimsa, pointing to a wardrobe. Between 20 and 30 buildings, including the school, were set ablaze in the government offensive on the village in central Syria on Thursday that the Syrian Observatory for Human Rights says left more than 150 dead. \"People had their throats slit here,\" the man said on Sunday during a tour of the home of the family of Shada al-Younes al-Mostafa, a known supporter of the rebels fighting President Bashar al-Assad. Several badly burned bodies still lay inside, three days after what the opposition alleges was a regime massacre of civilians. Human remains, torn apart by a grenade blast, filled a corner of the garden. According to the accounts of residents, most of the killings were carried out by shabiha pro-regime militiamen who had also made many arrests. A number of homes were targeted and then blasted by army tanks before the shabiha moved in to loot and burn, they said. UN observers entered Treimsa on Sunday to continue investigations, after they saw blood and evidence of the use of heavy weapons as well as burned out homes during a trip to the village on Saturday. They did not give a casualty toll. \"On the basis of this preliminary mission, UNSMIS can confirm that an attack, using a variety of weapons, took place in Treimsa on July 12,\" said Sausan Ghosheh, spokeswoman for the UN Supervision Mission in Syria. \"The attack on Treimsa appeared targeted at specific groups and houses, mainly of army defectors and activists. There were pools of blood and blood spatters in rooms of several homes together with bullet cases,\" she said. \"The UN team also observed a burned school and damaged houses with signs of internal burning in five of them,\" Ghosheh said, adding that a \"wide range of weapons were used, including artillery, mortars and small arms.\" At a news conference in Damascus, foreign ministry spokesman Jihad Makdissi said on Sunday that \"only five buildings where there were very sophisticated weapons were targeted.\" \"What happened was not an attack by the army on innocent civilians,\" said Makdissi, giving a death toll of 37 gunmen and two civilians. \"The aim of this news conference is to tell people that what happened was not a massacre... It was a clash between regular forces and armed groups who do not believe in a peaceful solution. This is the reality, politically and militarily.\" Makdissi staunchly denied reports that the army had used aircraft in the assault. \"This is absolutely not true. Only troop carriers and lights weapons were used, the most powerful of weapons being RPGs (rocket-propelled grenades).\" In Treimsa, at the home of English teacher Mahmud Daroish, residents said they pulled out dozens of bodies after the army assault, some of who had their throats slit or been executed with Kalashnikov assault rifles. On the walls of homes and shutters of shops, soldiers appear to have left behind their warnings: \"Bashar is president or we will burn down the country! ... You are the rats and we are the eagles.\" About 40 graves were hastily dug in the village on Friday, each containing three bodies, according to residents.