The 15-year-old Christian teenager was kidnapped in February by Boko Haram in Dapchi in Yobe state, Nigeria, along with 109 of her classmates.
While five died during the ordeal and the rest were freed, it's been reported Leah's captors kept her because she refused to convert to Islam.
In the clip released by a Nigerian news agency The Cable, Leah, who is seen in pictures wearing a hijab, asked for help in the Nigerian Hausa language.
"I am Leah Sharibu, the girl that was abducted in GGSS Dapchi. I am calling on the government and people of goodwill to intervene to get me out of my current situation," she said.
"I also plead to the members of the public to help my mother, my father, my younger brother and relatives. Kindly help me out of my predicament. I am begging you to treat me with compassion, I am calling on the government, particularly, the president, to pity me and get me out of this serious situation. Thank you."
Sources told The Cable that the audio and pictures provided were part of the proof of life requirement needed to renew negotiation efforts between the government and the Islamic State West Africa Province, which is the breakaway faction of Boko Haram that kidnapped the schoolgirl.
President Muhammadu Buhari's spokesman Garba Shehu said the secret service was analysing the voice recording and would share its findings after the investigation.
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