HANGU: At least four security personnel were killed and three others wounded in an Improvised Explosive Device (IED) explosion in Lower Kurram Agency's Shabak area near the Pak-Afghan border on Thursday.

Security personnel were transporting water and rations for troops stationed at the Pak-Afghan border when the vehicle they were travelling in was targeted in the blast.

Those killed included one Levies person and three army soldiers.

Political administration and military sources confirmed the casualties.

Security personnel reached the blast site and cordoned off the area as a probe into the incident went under way.

Lower Kurram is one of the most sensitive tribal areas as it borders three Afghan provinces and at one point was one of the key routes for militant movement across the border.

The region was claimed by the military to have been cleared of insurgents during an operation a couple of years ago, however, militants still carry out sectarian attacks and also target security forces occasionally.