BEIRUT - Seventeen people, including 10 women, were killed overnight by shelling in the southern Syrian town of Deraa, where the uprising against Syrian President Bashar Assad erupted 15 months ago, the Syrian Observatory for Human Rights said.The group, which monitors violence in Syria through a network of sources inside the country, reported fighting in the town between the army and rebels after the shelling.In the capital Damascus, which was once relatively secure from the unrest, it 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 Deraa was blocked by burning tires, it said.In addition to the deaths in Deraa, 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.Some 300 UN observers are in Syria to monitor a truce between Assad's forces and rebels that envoy Kofi Annan declared on April 12 but was never implemented.Now reduced to observing the violence, they have already verified the massacre in Houla, a town where 108 men, women and children were slain on May 25. The UN peacekeeping chief said Syrian troops and pro-Assad militia were probably responsible.As more and more civilians flee their homes to escape fighting, sick or wounded people are finding it hard to reach medical services or buy food, said a spokesman for the International Committee of the Red Cross (ICRC) in Geneva."The gunfire is so loud I think some bullets could have hit the house. I'm afraid to go out to see what is happening," one Damascus resident said. Activists said rebels attacked security barracks and shabbiha gunmen had been called in to help confront them.Three people were also killed in the capital's Qaboun district, according to the group. It also reported a large explosion in eastern Damascus.The state news agency said "terrorists" caused a fire in Qaboun's electricity station, which serves the Damascus region, knocking out four transformers and cutting power to some areas.Electricity Minister Imad Khamis said the fire caused $3 million of damage and would take three days to repair.One resident said a large sports venue, the Abbasid stadium, had been transformed into an army barracks as the military tried to reinforce the capital, and that increasing numbers of checkpoints had been set up.Earlier, a car bomb aimed at a bus carrying security men exploded in a Damascus suburb, killing at least two, the human rights watchdog said.Another car bomb hit a police branch in the northwestern city of Idlib, killing at least five people, it said.Elsewhere, government forces shelled and then tried to storm the rebel-held district of Khalidiya in the central city of Homs, the heart of the revolt against Assad, the NGO said.Activists said 10 rockets a minute crashed into Khalidiya in one of the fierce bombardments to hit Homs. Videos posted on the Internet showed plumes of grey smoke rising from buildings.Activist footage of protests said to be in the northern city of Aleppo showed crowds fleeing from tear gas and gunfire."The Syrian people are bleeding," Ban said at the United Nations on Thursday, warning of an "imminent" civil war.