KARACHI A roadside blast at University Road on the second consecutive day on Saturday claimed a life. The blast took place near the main gate of Karachi University, wounding critically a bicycle rider who happened to ride past the varsity. He succumbed to his wounds at the hospital. According to police, the terrorists had planted an explosive device in the green belt of the road. On Friday, a similar explosion occurred at the same road near Safora Chowrangi, killing three Rangers personnel and wounding four others. The investigators have so far been unable to make any headway but believed the involvement of a same group behind all four blasts carried out this week at different locations in the city. Police sources informed different investigating agencies were trying to track down the group involved in the current wave of terrorism and took into custody several suspects. Additional IGP Karachi Ghulam Shabbir Sheikh when contacted confirmed the arrests but declined to give any details. Following the Saturdays blast, Rangers and police cordoned off the entire locality. A bomb disposal squad official said the explosive device was similar to the one used in Fridays Safora blast and it was a low-intensity improvised explosive device.