Yousif Ibrahim no longer travels by night along the roads around his hometown of Jalawla in northeastern Iraq. He fears getting caught up in attacks by the Islamic State group.

¡°The police and army don¡¯t come into our area much anymore. If they do, they get shot at by militants,¡± said the 25-year-old, who sells fish for a living in a nearby market.

Nearly three years after the group lost its final enclave, Islamic State group (IS) fighters are re-emerging as a deadly threat, aided by the lack of central control in many areas, according to a dozen security officials, local leaders and residents in northern Iraq.