A suicide bomber, wearing a woman's burka, has killed at least 15 people in an attack at a busy police checkpoint in north-west Pakistan, officials say.
There have been a spate of attacks against the military
Four policemen were among the dead, and at least 20 people were injured in the blast in the garrison town of Bannu.
The bomb was detonated in a rickshaw, which had been stopped for inspection.
It is the latest in a series of deadly attacks blamed on Islamist militants in the North Waziristan tribal region near the border with Afghanistan.
Police officials said the bomber was wearing a burka, a woman's garment which covers the body from head to toe.
He, or possibly she, set off explosives at a busy intersection when police approached to check the vehicle.
Bombings and attacks have soared since July when security forces stormed a radical mosque in Islamabad, and a ceasefire with pro-Taleban militants in the volatile border area broke down.
Many of the attacks have been directed at the security forces. More than 200 soldiers and policemen are said to be among the dead.