KHAR, August 19 - Air strikes targeting suspected Tailban hideouts in a restive tribal district of northwest Pakistan killed 48 militants on Tuesday, the military said, as six civilians died in a roadside bomb attack.

The armed forces have since June been waging an assault to wipe out strongholds of the Pakistani Taliban and other militants in North Waziristan and other tribal areas, killing at least 600 insurgents according to the military.

An initial round of strikes killed 18 militants on Tuesday morning, a statement from the armed forces said, and 30 more died in later attacks from helicopter gunships.

"Five hideouts were wiped out in Khyber and seven were eliminated in North Waziristan," the military said.

Security officials said a house belonging to Taliban commander and Al-Qaeda-linked warlord Hafiz Gul Bahadar was destroyed in the strikes. Bahadar had already fled the area, officials said.

The roadside bomb attack was mounted in the Salarzai area of Bajaur, another tribal area on the Afghan border which has recently been attacked by militants from across the frontier.

Officials said the dead included three female schoolteachers and two of their infant children.

"According to initial reports, six civilians, including three lady teachers, two children and one passer-by have embraced shahadat (martyrdom)," a security official said.

Local administration official Sohail Khan confirmed the incident.

Another official in Peshawar said the van was carrying the women and their children to a community school run by an aid group funded by international charities.

No group claimed responsibility, but Islamist militants hiding in the lawless border areas have carried out such attacks in the past.

Pakistani jets and artillery began hitting rebel targets in mid-June to try to regain full control of the district and ground forces moved in on June 30.

Access to the areas where the offensive has been waged is strictly controlled, making it impossible to verify the number and identity of those killed in the fighting.

The assault was launched after a dramatic attack by insurgents on Karachi airport that killed dozens of people and marked the end of a faltering peace process with the Pakistani Taliban.