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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Darth Vader actor David Prowse has reprised his role as the Green Cross Code Man - 40 years after the original campaign ended.
The TV chef claims his father-in-law "forged" his signature to make him personally liable to pay £640,000-a-year rent on a pub.
Rain is forecast to hit most parts of the country this evening with a weather warning in place for Northern England and southern Scotland.