In an audio which surfaced online yesterday, Sharibu called on President Muhammadu Buhari to save her from captivity.
Sharibu was kidnapped alongside 118 students at Government Girls Secondary School, Dapchi, Yobe state, in February.
Shehu said Buhari’s administration would act after receiving briefing from the DSS on the audio.
He wrote on Twitter: “We are aware of the audio in circulation concerning the unfortunate situation of our daughter, Leah Sharibu.
“In dealing with terrorists, nothing is too trivial. The secret service is analyzing the voice. Our reaction will follow the outcome of the investigation.
“For President Buhari, nothing will be spared in bringing all our girls home. He will not rest until all of them are freed.”