ISLAMABAD, Pakistan (CNN) -- Police moved to dissipate possible sectarian violence after a suicide bombing in the middle of a Shia funeral procession killed at least 27 people and injured 75 others in Pakistan's North West Frontier Province Friday morning, police said.
Authorities are investigating and have imposed a curfew, said Mohammad Ramzan, a police investigator in the town of Dera Ismail Khan.
The attack took place along a major thoroughfare in Dera Ismail Khan, which has a history of violence between Sunni and Shiite Muslims. The army has been called in to maintain control, said Nasir Mehmud Sethi, a district police officer.
Sectarian violence has flared up recently with attacks on Shia processions in a part of the country where the Taliban have been expanding their influence. The Taliban are a fundamentalist Islamic group, primarily consisting of Sunni Muslims, that wants to impose a strict Muslim code of behavior on the region.
The attack came only days after Pakistan's government recognized the Taliban's interpretation of sharia, or Islamic law, in Swat and its surrounding district, located north of Dera Ismail Khan.
The agreement marked a major concession by the Pakistani government in its attempt to hold off Taliban militants who have terrorized the region with beheadings, kidnappings, death threats and the destruction of girls' schools.