A bomb Thursday killed two polio vaccination workers in Kurram, officials said, the latest in a series of such attacks which have now killed 19 in two months.
There has been no claim of responsibility for any of the killings. But the umbrella Taliban faction last year banned polio vaccinations in the tribal region of Waziristan, condemning the campaign as a cover for espionage.
"The two-men team was visiting Mali Khel village in upper Kurram tribal region when an improvised explosive device planted along the roadside went off, killing them on the spot," Jawad Ali, in charge of the campaign in Kurram, told AFP.
He said the team had been visiting different areas which were not covered by a three-day campaign that ended Wednesday. Local administration official Javaid Ullah confirmed the incident.