Seventeen people, including 10 women, were killed overnight by shelling in the southern Syrian town of Daraa, where the uprising against President Bashar Assad erupted 15 months ago, the Syrian Observatory for Human Rights said.
Meanwhile, UN observers who on Friday visited the site of a reported massacre in a Syrian village saw indications that government forces had been there and traces of slaughter in some of the houses, the United Nations said.
The Syrian Observatory for Human Rights, which monitors violence in Syria through a network of sources inside the country, reported fighting in Daraa between the army and rebels after the shelling overnight.
In the capital Damascus, which was once relatively secure from the unrest, the group said explosions were heard overnight after some of the fiercest fighting between rebels and security forces loyal to Assad. The main road south from Damascus to Daraa was blocked by burning tires, it said.
In addition to the deaths in Daraa, the Observatory said 44 civilians were killed across the country on Friday, nearly half of them in the central province of Homs and in Damascus districts and suburbs.
Twenty-five soldiers were also killed on Friday, it said, in the provinces of Idlib, Damascus, Deir al-Zor, Homs and Daraa.
Signs of carnage
United Nations monitors issued a statement on their visit to the Syrian hamlet of Mazraat al-Qubeir, where opposition activists say at least 78 people were massacred on Wednesday.
"Mazraat al-Qubeir was empty of its own residents and thus the observers were not able to talk to anyone who witnessed Wednesday's attack," the statement said.
It said armored-vehicle tracks were visible in the vicinity and some homes were damaged by rockets from armored vehicles, grenades and weapons ranging in caliber. Only the Syrian army has armored vehicles and heavy weapons.
"Inside some of the houses, blood was visible across the walls and floors," the statement said. "Fire was still burning outside houses and there was a strong stench of burnt flesh."
"The circumstances surrounding this attack are still unclear," it added. "The names, details and number of those killed are still not confirmed. The observers are still working to ascertain the facts."
The UN observers had been trying to reach the tiny farming village of about 150 people since Thursday but had been shot at and turned back by both security forces and residents.
Some 300 UN observers are in Syria to monitor a ceasefire between Assad's forces and rebels that was declared by peace envoy Kofi Annan on April 12 but never implemented.
A recent massacre in the town of Houla claimed the lives of at least 108 men, women and children. The United Nations has said it believes Syrian government forces and allied militia perpetrated the Houla killings.
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