A bomb blast at Quetta-Sibbi railway track wounded four railway officials and suspended the railway traffic, while another bomb explosion was reported in Mastung, on Saturday. Unidentified persons detonated explosives between Saryab and Spezinder railway stations, damaging a portion of the Pakistan Railways Bridge number 315 late on Friday night. Geo TV reported that when the railway staff reached the spot for repair work the next morning, another bomb went off at the track. The blast wounded four staff members. Two of the four injured workers, Aziz Khan and Ishaq, were shifted to CMH Quetta for treatment. The other two, Akhtar and Jameel, were shifted to Railway Hospital. Meanwhile, a bomb disposal squad diffused another bomb planted near the track. According to railway officials, Chiltan Express had been stopped at Quetta station till security clearance. Similarly, Bolan Mail from Karachi had been stopped at Kawalpur railway station. The repair work at the track will be resumed after security clearance, according to sources. Another explosion occurred near a bank at the main chowk of Mastung Town on Saturday morning, shattering windowpanes of nearby buildings. No casualties were reported in the incident.