LAGOS, Nigeria—Nigerian security forces are searching for armed gangs who killed 47 people in attacks in recent days in rural areas of the country’s northwest, the latest killings in the troubled region. The attacks took place in the northwest Kaduna state which neighbors Nigeria’s capital city, Abuja, Kaduna commissioner for security Samuel Aruwan confirmed. No group has claimed responsibility for the attacks but they are suspected to be by the gangs of bandits who have killed at least 2,500 people in the northwest and central states so far in 2021, according to statistics collated by the U.S. Council on Foreign Relations. The attacks have escalated in the past three months so the death toll for the entire year is expected to increase. The armed groups mostly consist of young men from the Fulani ethnic group who had traditionally worked as nomadic cattle herders and have become caught up in a …