MAKIN/MIRANSHAH (INP) - At least four militants were killed in a retaliatory fire of the security forces on Tuesday while one soldier was killed and another sustained injuries in an Improvised Explosive Device (IED) blast in tehsil Laddah of South Waziristan Agency (SWA). Official sources said security forces were on routine patrol in tehsil Laddah area of SWA when an IED planted on the roadside went off with a deafening sound, leaving a security man killed and inflicted injuries on another. The vehicle was also completely destroyed after hit by the IED. The injured soldier was shifted to hospital. Meanwhile, four militants were killed in a retaliatory attack by the security forces. A search operation was also launched in the area.