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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At least eight of the injured are said to be children who are thought to have been attending a birthday party at the Parc Monceau.
A competitive motorcyclist has died in a collision during a pre-TT race on the Isle of Man.
Greece's former finance minister told ITV News that Britain should remain in the EU and 'fight' to democratise it from the inside.