JOS, Nigeria (AP) — Attacks on villages surrounding a central Nigerian city at the heart of unrest between Christians and Muslims have killed more than 50 people this week, officials said Saturday, as authorities pleaded for peace over the Easter holiday.

The attacks around Jos, a city in Nigeria’s fertile central belt, come as a string of unsolved killings continue to plague the region that has seen thousands killed in massacres in recent years. While a combined police and military presence still patrols Jos and other parts of Plateau state, many of the villages attacked sit in remote, rural corners of the area that sometimes have only a single police officer on duty.