The United States on Tuesday condemned “in the strongest terms” the abduction of more than 300 schoolboys from their school in northwestern Nigeria and was investigating Boko Haram’s claim of responsibility, a spokesperson for the State Department said.

A man identifying himself as the leader of Nigeria’s Boko Haram, whose name means “Western education is forbidden” in the local Hausa language, said the Islamist group was behind the kidnapping which occurred on Friday at a secondary school in Nigeria’s state of Katsina.