Five bogies of Rawalpindi to Quetta Jaffar Express derailed on Monday after the railway track in Shikarpur detonated with explosives, leaving six passengers injured.
According to officials the injured have been shifted to a nearby hospital for medical attendance.
The terrorism incident happened near the Sultan Kot railway station in Shikarpur district of Sindh.
Security sources have said that the outlawed BLA has been involved in the railway line explosion incident.
The authorities have suspended the railway traffic temporarily.
Police have cordoned off the area of the incident and collecting evidence from the scene.
Railway officials have said that the relief teams have been summoned from Sukkur, which have been engaged in removal of the affected railway bogies and started repair of the damaged portion of the track.