Militants hit Pakistani security forces on the eve of a major international summit, killing 10 people in regional flashpoints yesterday as delegates arrived in the capital Islamabad.
In the southwestern city of Quetta, bombers hit an army vehicle escorting children home from school, killing four soldiers and a woman, police said.
More than 20 people were wounded when the bomb, planted on a motorcycle, was detonated by remote control, said Quetta city police chief Hamid Shakeel.
There was no immediate claim of responsibility for Wednesday's attack but Quetta and its province Baluchistan are frequently hit by bomb attacks.
In northwest Pakistan, five policemen were killed in two other attacks.
Four police died when gunmen ambushed a routine patrol in the Jani Khel area of Bannu district, Nisar Ahmed Tanoli, the local police official, told AFP.
A roadside bomb in Shangla district also killed one police official and injuring four others, according to police.