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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A British citizen was likely taken to China against his will in a 'serious breach' of a bilateral agreement with the UK, a report says.
Atheist Richard Dawkins has cancelled his Australia and New Zealand tour after suffering from a 'minor stroke', his management said.
Sleet and snow for some parts of Scotland. Elsewhere in the UK will be cold, cloudy and with some showers.