A Nigerian military plane flying from Benin City to Lagos crashed on Monday in southwestern Ondo state, killing 25 passengers and seven crew members.
President Bola Tinubu, confirming that there were no survivors, expressed "profound sadness" and extended condolences to the families of those aboard.
"The Chief of Air Staff has briefed me, and I have directed the Nigerian Air Force to immediately commence a thorough investigation into the cause of the crash to prevent future occurrences," Tinubu said in a statement.
The Air Force ATR-42 aircraft was on a routine mission from Benin City to Lagos when air traffic controllers lost contact with it at 0813 GMT on Monday, Aviation Minister Festus Keyamo said.
The accident was one of the deadliest air disasters in Nigeria in recent years.
The wreckage was later located near the coastal town of Igbokoda, where search and rescue teams were deployed.

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