The father of a British man killed in a siege at an Algerian gas plant has not "forgiven or understood" his son's death, an inquest has heard.
Stephen Green was one of six British workers taken hostage and then killed at the In Amenas plant in January 2013.
The inquest at the Royal Courts of Justice was told how jihadists "encouraged" the captives to call or send messages home before they died.
Forty workers and 29 militants were killed during the siege.
The inquest is examining the deaths of Mr Green, 47, from Hampshire; Garry Barlow, 50, from Liverpool; Carson Bilsland, 46, from Perthshire; Sebastian John, 26, from Norfolk; Paul Morgan, 46, from Liverpool and Kenneth Whiteside, 59, from Fife.
It is also examining the death of Carlos Estrada, a Colombian who had moved to London.
The attack unfolded over four days when 34 armed men from the Signed-in-Blood Battalion ambushed a bus carrying workers from the plant in the Sahara desert.
It ended when Algerian forces regained control in a bloody final assault.
Opening the inquest, assistant coroner for West Sussex, Nicholas Hilliard QC, said: "Each and every death is a wholly separate tragedy and leaves family and friends devastated and bereft."
Mr Green's father, David Green, said: "Stephen's death has been very hard for us. He had a lot of happiness to look forward to.
"I feel both grief and anger - grief that my son was refused a happy future, and anger against those responsible.
"They are not forgiven or understood."
Christopher Bilsland, younger brother of one of the victims, told the court "monetary gain had been valued over human life" at the plant.
The inquest heard that Carlson Bilsland had written about working at In Amenas: "The job is fine but security is not good and not safe compared to other places I've worked."
The inquest was told the men were urged by their captors to make contact with the outside world in order to publicise their demands that 100 Islamist prisoners in Mali be released.
Det Supt James Stokley, the senior investigating officer, told the court how one of the hostages, 26-year-old Mr John, had sent photographs of the attackers home.
While he was being held he had the "presence of mind to make and send pictures of his captors... at considerable risk to himself", the officer said.
Another of the British men, Mr Whiteside, was said to have headbutted one of the jihadists, before being overpowered and handcuffed, the court was told.
Once the plant had been seized, the hostages were held together with explosives attached to them.
Many of the men were last seen alive being put on vehicles by the armed men on the second day of the siege.
"The terrorists said they had placed bombs in each vehicle which would explode if they were attacked by the military," Det Spt Stokley told the inquest.
The following day witnesses described seeing vehicles that had been blown up and Mr Barlow's body.
The 50-year-old father of two, along with Mr Bilsland and Mr Whiteside died from injuries caused by an explosion, according to post-mortems carried out in the UK.
Mr John died after a blunt injury to the head, Mr Morgan by a gunshot wound to the head and Mr Green from a gunshot to the chest.
BP executive Mr Estrada died from multiple gunshot wounds and injuries caused by an explosion.
Pictures of the victims were shown on a screen as their relatives gave evidence.
Mr Barlow's wife Lorraine, told the court the attack had begun on her husband's 50th birthday.
"I need to understand why this happened to such a wonderful man," she said.
Last week, the inquest's coroner stood down to be replaced by Judge Hilliard after the government said it might present "sensitive material" as evidence.
16 January 2013 Militants attack two buses carrying In Amenas workers, killing two. They then go on to the living quarters and main installation, seizing hostages. Some gas workers manage to escape
17 January Algerian forces attack after the militants try to move their hostages in five 4x4s. Four of the vehicles are destroyed in an air strike and an unknown number of hostages are killed
18 January Stalemate as Algerian forces surround the gas plant where the remaining hostages are held
19 January Algerian forces launch a final assault after reports that the hostage-takers are killing their captives
The six British victims were among 40 workers killed at the plant.
Militants arrived before dawn on 16 January last year and entered the In Amenas plant, a joint venture run by British company BP, Norway's Statoil and Algerian state company Sonatrach.
Within 15 minutes they had taken control, killing some some of the plant's 800 workers and taking others - mostly foreigners - hostage.
Algerian forces surrounded the site and, while militants were moving hostages in a convoy, destroyed four vehicles - killing an unknown number of hostages.
The Algerian army finally regained control of the plant with an assault on 19 January.
The hearing is expected to last until the end of next month.