BEIRUT – Syrian fighters killed 21 members of the elite Republican Guard in Damascus province Thursday, as the army subjected several districts of second city Aleppo to fierce shelling, a monitoring group said. The Syrian Observatory for Human Rights said the toll of Republican Guards killed in the town of Qudsaya, west of Damascus, may rise beyond 21, given the ferocity of the violence. “The rebels likely used a small explosive device, but it was placed near the Republican Guards' living quarters in Qudsaya,” said Observatory director Rami Abdel Rahman, who added that clashes were continuing after the blast. The attack occurred a day after the army launched a major offensive on Qudsaya and a neighboring locality, the Observatory said. Also in Zabadani, northwest of Damascus, the army and rebels clashed, said the Observatory. “The quality of operations staged by the rebels is improving,” said Abdel Rahman. “This is especially noticeable in Damascus province, which is strategic for both the rebels and the regime because of its proximity to the capital.” Amid the violence, regime forces carried out a large number of arrests in Qudsaya, the Observatory said. In Aleppo, the army shelled the Nayrab, Salaheddin, Mashhad, Bab Al-Nasr and Sakhur districts. The districts are spread across the city. – Agencies