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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Babies born at weekends in NHS hospitals are more likely to die in their first week than those delivered on weekdays, new research suggests.
A 16-year-old boy has died after an "altercation" between a group of men in Leicester.
The Chancellor will present his Autumn Statement and Spending Review to the House of Commons on Wednesday.