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 pregnant woman and a man suffered "severe discomfort" after someone threw bleach at them from a passing car, hitting them in the eyes.
A look at the weather today across the UK.
Former child star Erin Moran who played Joanie Cunningham in the US sitcom "Happy Days" has been found dead at 56.