The suicide bomber who blew herself in front a security post calmly lifted her veil and smiled before detonating the explosives when she was stopped by the personnel in Peshawar, a media report said.
Officials believe the woman, who blew herself up on Tuesday near a check-post in the high security cantonment area in the capital of the North West Frontier Province, was an Afghan as she was clad in an all-enveloping, blue burqa normally worn by Afghan women.
A Military Police personnel challenged the woman when she was 20 meters from his post. He pointed his gun towards her when she did not stop and identify herself, an official said. The woman then unveiled her face and blew herself up while she was about 15 meters from the post.
"She lifted the veil from her face and smiled and then there was a huge explosion," a security official was quoted as saying by the Dawn newspaper.
Pakistan has witnessed more than 25 suicide bombings this year, a majority of them in the northwestern region where troops have been fighting pro-Taliban militants, but this was the first such attack carried out by a woman. There were no casualties in the bombing.
Newspapers carried a picture of the woman, who appeared to be in her thirties and had long black hair. Her face, torso and legs were largely intact and only her abdomen was blown apart by the explosion.