Boko Haram picking up where the Pakistani Taliban left off.

KANO, Nigeria (AP) — Gunmen suspected of belonging to a radical Islamic sect shot and killed at least nine women who were taking part in a polio vaccination drive in northern Nigeria on Friday, highlighting the religious tensions surrounding the inoculation of children in one of the few nations where the disease still remains endemic.

The attack shocked residents of Kano, the largest city in Nigeria’s predominantly Muslim north, where women often go from house to house to carry out the vaccination drives as Muslim families feel more comfortable allowing them inside their homes than men. It also signaled a new wave of anger targeting immunization drives in Nigeria, where clerics once claimed the vaccines were part of a Western plot to sterilize young girls.

The first attack Friday morning happened in Kano’s Hotoro Hayi neighborhood and saw gunmen arrive by three-wheel taxis and open fire. At least eight female vaccinators died in that attack, witnesses said.

The second attack, in the Unguwa Uku neighborhood, saw another four people killed, witnesses said. The witnesses spoke on condition of anonymity out of fear of angering the radical sect known as Boko Haram.