Boko Haram jihadists Photograph:( AFP )
The sources said the Islamic State West Africa Province (ISWAP), a rival militant group to Boko Haram, had released the hostages after finding them in a Boko Haram camp
Ten people who had been held captive by Islamist militants were freed this week in northeast Nigeria's Borno state, three security sources and two close associates of those released told Reuters.
The people, including aid workers, had been taken by Boko Haram over the past year, the sources said. They were released at around noon (1100 GMT) on Monday and were taken to a hospital in Borno state capital Maiduguri.
The sources said the Islamic State West Africa Province (ISWAP), a rival militant group to Boko Haram, had released the hostages after finding them in a Boko Haram camp, but it was not immediately clear why they released them.
An army spokesman did not immediately respond to a request for comment.
UNHCR spokesman Roland Schoenbauer confirmed that one of their staff workers, Idriss Abubakar Garba, who was abducted on the Maiduguri-Damaturu highway road in January, was among those released.
"We are relieved at his safe return," Schoenbauer said when reached by phone.
Earlier this month, a person purporting to be ISWAP leader Abu Musab al-Barnawi said in an audio recording that the leader of Boko Haram, Abubakar Shekau, had died around May 18 after detonating an explosive device when he was pursued by ISWAP fighters following a battle.
Political analysts said Shekau's death could lead to the end of a violent rivalry between the two groups, enabling ISWAP to absorb Boko Haram fighters and consolidate its hold on territory in northeastern Nigeria.