PESHAWAR, Pakistan (AFP) - A bomb wounded 11 people, mostly children, when it exploded outside a Pakistani girls' school on Thursday, a doctor said.

The bomb went off at the end of the school day as pupils walked into a street lined with fabric shops in the north-western town of Bannu, which has been a flashpoint for Islamist militancy.

Dr Omar Zeb told AFP that 11 people had been brought to the local hospital - seven primary schoolgirls and four other people who had been outside in the street.

Police official Azad Khan told AFP that at least four girls, two boys and a man had been wounded. Three of them are in serious condition, he said.

There was no immediate claim of responsibility, but Islamist militants frequently attack girls' schools - usually when the buildings are empty in the evening or during the holidays.

Last October the Taleban shot schoolgirl activst Malala Yousafzai in the head in the north-western Swat valley.

She has largely recovered and now lives in England, where she is enrolled at a private school and has become a global icon for children campaigning for the right to an education.