More than 27,000 people have been killed in attacks in northeastern Nigeria since 2009, the United Nations said.

“The humanitarian crisis in northeast Nigeria is one of the most severe in the world and is first and foremost a protection crisis,” Edward Kallon, the UN humanitarian coordinator in Nigeria, said in emailed statement.

“Women, men and children face grave violations of human rights and international humanitarian law every day.”

The UN condemned Sunday bombings by suspected Boko Haram insurgents that killed at least 30 people in attacks in Konduga town in northeast Borno state.

Among those killed was a community volunteer who was contributing to the humanitarian response in the region, according to the UN. It called on Nigerian authorities to prosecute those responsible for the attacks and ensure justice is done.

Boko Haram has been waging a violent campaign in Nigeria to impose its version of Islamic law. The country is Africa’s top oil producer and most populous nation, with more than 180 million people.