MIRANSHAH: A remote-controlled bomb attack on Sunday killed three soldiers in Pakistan's troubled Waziristan district, where Islamabad has resisted US pressure to launch a full-scale offensive against an insurgency.

Pakistan security officials said the bomb targeted a military convoy which was moving from Mirali town to Miranshah, the main town of North Waziristan tribal district, which has become the most notorious Taliban and al Qaeda stronghold on Pakistan's border with Afghanistan.

“Three soldiers were killed and three were wounded in the blast. Their vehicle was completely destroyed,” a senior security official based in the region's main Peshawar city told AFP.

Another senior security official confirmed the incident and death toll, adding that a second military vehicle was also badly damaged.

Islamabad has told Washington that US forces must seal the Afghan border in the event of any offensive against the al Qaeda-linked Haqqani network in North Waziristan, an official said Saturday.

The Haqqanis, blamed for some of the deadliest attacks in Afghanistan and whose leaders are understood to be based in the Pakistani tribal district, is one of the thorniest issues between Islamabad and Washington.