Nigeria's government said 104 of the 110 schoolgirls had been confirmed freed.
Amnesty International has expressed relief following the news of the release of some of the girls abducted last month at a secondary school in Dapchi, Yobe State.
When asked how a boy came to be among the released girls as the school they were abducted from was a female school, the Minister said, "I can tell you that is authentic".
"Many of the girls that were released were not dropped in one place".
"When I get there we will do a head count to see if all of them have been released", said Bashir Manzo, whose 16-year-old daughter was among those kidnapped during the February 19 attack.
"Right in front of us, the militants brought the girls and dropped them and then left", he said.
He said the release of the schoolgirls is the outcome of the directive by President Muhammadu Buhari to all security agencies to do everything possible to secure the release of the 110 Dapchi schoolgirls, who were abducted 19 February 2018.
"Based on that, the Federal Government with support of friendly countries embarked on back term negotiations; this back term negotiation has led to the release of these girls".
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Russian Federation denies involvement in the March 4 attack in the English city of Salisbury. "This took place on the territory of Great Britain", he said. "You can expect to be assassinated.
He said some of the girls, aged between 11 and 19, looked "panicked" initially and could barely respond to questions.
Mr Amharic M-grah, whose daughters were among those abducted, told TheCable that his children were brought back on Wednesday morning.
"Reports say that 5 of them may have passed on, and 1 is still held back".
The speaker said intelligence gathering must be strengthened to prevent attacks before they occur.
"The only condition they gave us is not to release [the girls] to the military but release them in the town of Dapchi without the military presence", Mohammed told Reuters in Abuja.
The extraordinary development brought elation to most of the families, but more heartache for the relatives of the six girls still unaccounted for.
The group's National Publicity Secretary, Muhammad Ibrahim, in a statement, commended the Federal Government for the effort, adding that the group received the "good news" with huge happiness. Some 100, however, are believed to remain in captivity. "Any report that we paid ransom or engaged in prisoner swap is false", he said. Thank God for the safe return of our sisters.