At least 30 people, including civilians and members of the military, have died after an attempted rescue of an oil exploration team kidnapped by suspected Boko Haram militants in northeast Nigeria, officials told Reuters on Thursday.

The team searching for oil in Nigeria’s conflict-ridden northeast was made up of members from the state oil firm and university researchers and staff, while the attempted rescue was carried out by military personnel and vigilantes.

The military said a day earlier that it had recovered the bodies of nine soldiers and a civilian during its rescue of staff from the Nigerian National Petroleum Corporation (NNPC) who were on the survey team.

The total number of military personnel killed was 12, said one military source in Nigeria’s northeast, who declined to be identified because the source was not authorised to speak to media.

The military’s statement on Wednesday did not refer to team members from the University of Maiduguri, which contributed staff including geologists to the team surveying in the Lake Chad Basin region.

A spokesman for the university, Deputy Director of Information Ahmed Mohammed, said on Thursday two university academics and at least one driver were among at least five dead.

Four others staff members from the university are missing, he said.

Sixteen members of the Civilian Joint Task Force (CJTF) were also killed, Bunu Bakar, secretary of the armed vigilante group, told Reuters.

Nigeria’s oil minister said he was awaiting official confirmation from military authorities on the kidnapping and attempted rescue of people including NNPC staff, declining to comment on the death toll.

A military spokesman did not reply to phone calls and text messages requesting comment.

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