Funerals have taken place in the Swabi area of north-west Pakistan for seven charity workers, six of them women, who were gunned down on Tuesday.
The workers, some of them teachers, were attacked near a children's centre.
Correspondents say it is not clear if they were targeted because their charity offered vaccinations or education for girls.
Militants have targeted polio vaccination programmes before and are also opposed to girls' education.
But no group has said it carried out this attack.