British officials had worked for months trying to track down the captured men as rumours floated that they had been taken out of the country.
Nigerian government sources said that the men were killed before the arrival of security forces.
The wife of one of the guards holding the hostages in Nigeria claimed they were taken into a toilet and shot dead during the failed rescue attempt.
Today's hearing will take place at Wiltshire and Swindon Coroner's Court in Salisbury.
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Declan Donnelly is reportedly tying the knot with his manager partner Ali Astall in Newcastle today.
Warming up in the south but with breezy showers across Scotland today.
BA passengers face tighter curbs on the size of hand luggage as part of inclusive allowances for economy and premium economy travellers.