ISLAMABAD, Jan. 8 (Xinhua) -- At least four soldiers were killed and two others injured when a bomb went off in Pakistan's northwest tribal area of Lower Kurram Agency on Thursday morning, local media reported.

Dawn TV said that the incident happened when a security forces' vehicle hit a landmine in Shabak area of Lower Kurram, a semi- autonomous tribal area along the Pakistan-Afghanistan border.

The vehicle which was carrying troops to their duties was completely destroyed in the blast.

The injured people have been shifted to a nearby hospital.

No group has claimed responsibility for the attack yet, and investigation is underway.