An Islamic cleric has been tipped to emerge as chief negotiator for Boko Haram as the group prepares for talks with the Nigerian government over its proposed exchange of its imprisoned members with over 200 girls it abducted April 14 from Government Girls Secondary School, Chibok, Borno State.

Boko Haram is at the same time preparing to announce a list of key militants that it wants released in exchange for the schoolgirl hostages, according to Britain’s Telegraph, quoting sources close to the terrorist group. The sources were quoted as disclosing that an Islamic cleric from northern Nigeria will be authorised to negotiate on behalf Boko Haram with the Nigerian government. The name of the cleric involved and of the key commanders to be freed is expected to be revealed as early as today, the report said.

It said that Boko Haram will give the cleric “clear terms of reference” for how it wants the negotiations to be conducted, and will also spell out the practical details of how it would set the girls free.

As well as senior commanders, the list of prisoners to be freed is expected to include a number of militants’ relatives who have been detained by Nigerian government to put pressure on the group’s leadership, The Telegraph reported.

It said that details of the proposed deal were revealed on Tuesday night by a source close to some of the militants’ families in the northern city of Maiduguri, where Boko Haram first started in the 1990s.

The source told The Telegraph: “The group are about to name a cleric who they will mandate to talk to the government. They will give him clear terms of reference, including a list of the members they want release, and details of how they will free the girls.

“The list will include personal relations who have been detained, but also top members of the group. In total, the numbers to be released will probably be equal to the number of the girls currently held.”

Details of the group’s demands follow the release of a video tape on Monday in which Boko Haram’s leader, Abubakar Shekau, paraded the schoolgirls before a camera and demanded a mass prisoner swap for his “brethren” in Nigeria’s jails. The girls, believed to number around 220 in total, were kidnapped from a school in Chibok, north-east Nigeria, a month ago.

Freeing Boko Haram fighters could involve putting men responsible for the deaths of hundreds of people back on the streets.

One senior militant currently in a Nigerian jail is Kabiru Sokoto, who was sentenced to life with hard labour last year for masterminding the bombing of a church outside Abuja that killed 44 people on Christmas Day 2011.

Another group of detained Boko Haram suspects is a gang accused of the kidnapping and killing of Chris McManus, 28, a British engineer who was abducted along with an Italian colleague, Franco Lamolinara, in northern Nigeria in May 2011. The pair were killed by their captors during a rescue attempt ten months later by a joint force of Nigerian troops and British special forces.

The eight men were arrested by state security police not along after the kidnapping, which was allegedly carried out on the orders Khalid al-Barnawi, the leader of an al-Qaeda affiliated Boko Haram faction called Ansaru. Both al-Barnawi and Shekau were designed by the US as terrorists in June 2012, and while the two are known have had fallings out, they are understood to have made amends.

In the past, a dialogue and amnesty committee set up by the Nigerian government has brokered the release of a number of Boko Haram detainees, mostly relatives of fighters still at large who were detained to put pressure on the fighters themselves.

Among those released last year was Shekau’s wife and children, who were detained during a raid in December 2012 in which Shekau was injured but escaped. While the amnesty committee has always insisted that the releases were humanitarian gestures, many suspect they were in fact the result of secret deals with Shekau, who is known to have kidnapped a number of police and soldiers in revenge for his wife being taken.

•Photo shows Boko Haram fighters on the way to an operation.

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