ABUJA, Nigeria — The Nigerian army said Sunday it freed 360 people abducted by Boko Haram in southern Borno, in the northeastern part of the country.

The operation, according to the army’s statement, was conducted in the Mandara mountains which form a part of the militant group’s stronghold. It resulted in the release of several people, including children, who had been abducted across different communities in Borno.

Two infants “succumbed to exhaustion” due to the challenging mountainous terrain and the hardship they endured during their prolonged captivity, an army spokesperson, Haruna Sani, said.

“The remaining rescued abductees were successfully evacuated to safe locations for medical care and humanitarian support, marking a major operational success and a significant setback for the terrorist group,” Sani said.

Nigeria faces a complex security crisis, especially in the north where a more than decade-long insurgency and the activities of armed groups that carry out kidnappings for ransom and illegal mining have heightened the country’s security challenges.

Among the most prominent Islamic militant groups are Boko Haram and its breakaway faction, which is affiliated with the Islamic State group and known as Islamic State West Africa Province.

Last month, the West African country said its joint operation with the United States had killed 175 ISWAP fighters.

The insurgency in Nigeria’s northeast has killed thousands of people and displaced millions, according to the United Nations. Analysts say not enough is being done by the government to protect its citizens, despite repeated promises by President Bola Tinubu to curb the crisis.