The current 300,000 Syrian refugees could become 700,000 by year\'s end, the Geneva-based UN High Commission for Refugees (UNHCR) made known on Thursday. There were 41,500 Syrian refugees registered in March, according to UNHCR. Also on Thursday, an oil pipe exploded and a pumping station manager was abducted by strangers in Tal al Bayda, in the Um Madfa area south of the city of Hasaka, in the province by the same name, the National Observatory on Human Rights in Syria reported. In a separate incident, a car bomb exploded at a government roadblock on the Aleppo-Damascus highway, near Tel Hadba village in Idlib province. New bombing raids were carried out in Damascus province, which were particularly intense over the towns of Zabadani, Ebada and Jdeidat Artouz, the Observatory said. Yesterday\'s 305 victims made it the bloodiest day since the uprising began in March 2011, according to Observatory figures. At least 22 people have been killed today in combat and in bombing raids, which are ongoing in Aleppo, Latakia, Homs, Idlib and Day az Zor provinces, according to Local Coordinating Committee activists. Also today, schools were closed in the small Turkish town of Akcakale, near the Syrian border, on fears of stray bullets from across the border, and fighting between rebels and government soldiers has intensified in the Syrian town of Tal Abyad, Turkey\'s Anadolu press agency reported. The rebels took control of the Tal Abyad border crossing ten days ago, after 24 hours of intense combat.