Four of the more than 200 Nigerian schoolgirls abducted last month from a village school by the Boko Haram insurgent group have escaped their captors, according to a local official, Nigerian newspaper reports.
Bana Lawan, chairman of the Chibok Local Government Area, said on Wednesday that the four girls escaped their captors on Tuesday, both the Daily Times and Punch newspapers report.
The Premium Times earlier quoted Lawan as saying that the girls had been freed after becoming ill. The Times initially reported the release on Twitter.
An unidentified senior official in Borno state official told Reuters, however, that the four girls fled "a little after the initial escapes" of 53 others, "but we doubt it was a recent escape."
The four have been reunited with their families, which did not contact the government, he added.
Lawan said the Islamist gunmen kidnapped 221 girls in mid-April as they took exams in the northeastern village of Chibok village in Borno state. Authorities said 164 are still in the hands of the militants.
The fundamentalist group, which the Obama administration has designated the group as a terrorist organization, has threatened to sell the girls if the Nigerian government does not exchange them for imprisoned Boko Haram comrades.
The reports of the abduction caused worldwide outrage. The United States has deployed surveillance drones, spy planes and about 30 civilian and military specialists to support Nigeria's security forces in the search for the missing girls.
Nigeria Chief of Defense Staff Air Marshal Alex Badeh said Tuesday that. officials know the whereabouts of the abducted girls.
"The good news for the parents of the girls is that we know where they are, but we cannot tell you," he said on Radio Nigeria. "We want out girls back, I can tell you that our military can and will do it. But we can't kill our girls in the name of trying to get them back."
The U.S. State Department said Tuesday that the United States could not confirm the Nigerian claim. Two weeks ago, the Pentagon confirmed that U.S. drones are involved in the search for the girls.
Nigeria's former president, Olusegun Obasanjo, has met with people close to the militant group to try to broker their release, the AFP news agency reports, quoting an unidentified source close to the talks.
The agency says the talks were held last week in southern Ogun state and included relatives of senior Boko Haram fighters.