Two Pakistani soldiers were killed and two more injured when their convoy was targeted with a roadside bomb in the restive South Waziristan tribal region near the Afghan border.
The bomb went off near the convoy when it was moving from Shakai to Wana, the main town in South Waziristan Agency, a Taliban stronghold, TV news channels reported.
No group claimed responsibility for the attack.
The Pakistan Army has deployed thousands of soldiers in South Waziristan for a planned offensive against Taliban fighters owing allegiance to slain commander Baitullah Mehsud.
Though preparations for the campaign were reportedly completed some time ago, no ground offensive has been launched as yet.
Artillery and combat jets have been used to bomb Taliban hideouts in the region, which is also considered a safe haven for Al Qaida. US drones have also carried out a wave of missile strikes in Waziristan, including one that killed Mehsud last month.