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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The Ministry of Defence has announced that the first British reservists have set off for Sierra Leone to help tackle the Ebola outbreak.
Wintry sunshine for most of the country today but some showers expected in the northwest.
A cyclist has cheated death after being hit by 4-wheel truck when he rolled down under it in East China's Zhejiang Province.