DRVARE, Serbia (Reuters) - Serb security forces battled separatist rebels for control of guerrilla strongholds in northern Kosovo on Monday as political representatives of the two sides began peace talks in Paris. Yugoslav security forces deployed in the village of Drvare, around 20 km north of the provincial capital Pristina, were firing heavy mortars west towards the Cicavica mountain range on Monday morning. Houses in Bencuk, a village on the lower slopes, came under fire and three homes in the village of Mijalic, shattered in a weekend offensive, were in flames. Fighting between Serb forces and ethnic Albanian Kosovo Liberation Army (KLA) guerrillas, who have clashed on and off over the area for three weeks, is now spread out along a 12-kmfront line. In nearby Priluzje, Serb police fired light cannons from armoured trucks at KLA positions and the rebels returned fire. The army also pounded Surdov Ridge, to the north, with rockets. A Reuters team on the ridge saw more shells landing on the village of Lubovac, scene of fierce clashes at the weekend. The death toll from a weekend of some of the worst violence in the year-long conflict in southern Serbian province has risen to at least 18. An official with the Organisation for Security and Cooperation in Europe (OSCE) monitors in Pristina said the monitors, who are unarmed, were being confronted with increased hostility from both sides. "Last week, somebody fired on one of our cars. The bullets came from VJ (Yugoslav army) positions," he said. "Yesterday, the KLA checked the documents of one of our teams to see if there were any Russians among them. They said they don‘t like Russians." The ethnic Albanian Kosovo Information Centre said on Monday four male members of an ethnic Albanian family had been killed by Serb police in the village of Grajkovac, north of Prizren in southwest Kosovo, as they went to fetch wood. At least eight people were killed in three bomb blasts in two Kosovo towns on Saturday and four KLA guerrillas died in a shoot-out with Yugoslav army forces during a day of heavy clashes in the Dus-Svrhe area. An OSCE official said there were reports another two dead men had been found in southern Kosovo, presumably shot during last week‘s violence. Earlier the monitors said fighting had broken out overnight in Luzane, also north of Pristina, with small arms fire continuing through the night. Yugoslav and ethnic Albanian delegations restarted internationally mediated peace talks in Paris on Monday that the West hopes will end more than a year of war in Kosovo. In the last year some 2,000 people have been killed and 600,000 forced from their homes in the province.