KANO, Nigeria (AP) — Radical Islamic fighters killed seven foreign hostages in Nigeria, European diplomats said Sunday, making it the worst such kidnapping violence in decades for a country beset by extremist guerrilla attacks.

Nigeria’s police, military, domestic spy service and presidency remained silent over the killings of the construction company workers, kidnapped Feb. 16 from northern Bauchi state. The government’s silence only led to more questions about the nation’s continued inability to halt attacks that have seen hundreds killed in shootings, church bombings and an attack on the United Nations.