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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Philip Hammond has dismissed concerns that abolishing stamp duty for first-time buyers will push up house prices.
Elsewhere it will be largely sunny, though with gusty winds at times, and a few showers likely in places.
Heavy rain has caused widespread flooding and travel disruption across north west England and North Wales.