A spokesman from the Nigerian military has retracted a statement that girls held in its custody are some of those from Chibok.

Major General Chris Olukolade on Tuesday confirmed rumours that some of the girls taken from their school in Borno state in April had been rescued and were now "safe in a military barracks".

However, he later withdrew this statement, revealing that the girls being held in the Maimalari Barracks, headquarters of the 7^th Division of the Nigerian Army in Maiduguri, are not in fact from Chibok.

A tweet from the Nigerian Army's Twitter account last night confirms Olukolade's retraction:

Last week, it was reported that a negotiation deal was close to being brokered with Boko Haram, the terrorist group that kidnapped the Chibok schoolgirls, to secure their release.

The International Committee of the Red Cross was said to be negotiating a prisoner swap, and had apparently been coordinating secret talks between the Islamist group and the Nigerian government.

President Goodluck Jonathan has previously claimed that his government will not negotiate with the terrorists, who have asked for the release of some of their "brethren", though an exchange deal was agreed last May.

It collapsed, however, and an estimated 220 girls remain in captivity, now over five months since they were taken on April 14.

Specialist teams from the UK, US, France and China have been sent to Nigeria to assist authorities in the rescue effort, but President Jonathan has faced criticism for what many see as a slow and inadequate response.

Boko Haram, which loosely translates to "Western education is forbidden", is thought to be responsible for the deaths of at least 13,000 people since it became active in 2009.