"The suicide bomber...exploded himself when police asked him to stop for a search at the Bara Qadeem check post," SSP Operation Abdul Ghafoor Afridi told reporters.
Six security personnel were killed by the explosion, and several schoolchildren were among the wounded. All of the injured were hospitalized, some of them in critical condition.
Several houses were damaged near the blast area, which was cordoned off by police.
The United States has expressed concerns over an increase in militant activity in Pakistan. More than 200 militants have been so far killed by the Pakistani security forces in the North-West Frontier Province.