Two security officers who were accompanying a polio vaccination team were killed in an attack in northwest Pakistan on Wednesday morning.
The attack was the latest in a series of similar attacks targeting the polio eradication drive.
According to a report by the authorities, the team was traveling to Lower Dir district about 112 miles from the capital Islamabad when they were ambushed by unknown gunmen.
The government said at least 104 cases were reported this year, an increase from 12 reported cases in 2018.
The authorities said the campaign has been hampered by attacks that have killed at least seven team members and policemen this year and about 98 since 2012.