Algeria hostages: Five Britons dead or unaccounted for
Five Britons and one UK resident have been killed or are unaccounted for after the conclusion of the Algeria kidnap crisis, William Hague has said.
This was in addition to the one British fatality which had already been confirmed, the foreign secretary said.
Prime Minister David Cameron said "the whole country shares my sympathy and concern" for those involved.
"It is our priority now to get people home as quickly as possible and to look after the survivors," he added.
Mr Cameron said he was told in a phone call from his Algerian counterpart that the hostage crisis at the remote In Amenas desert gas facility had ended.
The Algerian Interior Ministry later confirmed that 23 hostages and 32 terrorists had been killed, and that 107 foreign workers and 685 local employees had been released.
"There is no justification for taking innocent life in this way," Mr Cameron said.
"Our determination is stronger than ever to work with allies right around the world to root out and defeat this terrorist scourge and those who encourage it."
'Appalling and unacceptable'
The families of those who were taken hostage had been contacted, said Mr Hague.
He added: "We understand that the site is not yet fully safe because of hazards such as booby traps, and so they are still working on that.
"We've had a team in the vicinity today, led by our ambassador who went down from Algiers, they have been helping British nationals to get away from the area, working with other countries and co-ordinating with the Algerian authorities."
BP's chief executive Bob Dudley said the hostage incident was a "distressing and horrific time".
"At the time of the events in Algeria, there were 25 nationalities represented on the work site," he said.
"BP had 18 expatriates, and today we are able to confirm the location and safety of 14 of those people.
"Sadly, we're not able to confirm the locations or circumstances of four of our employees. Tragically, we have grave fears that we may have fatalities from this group."
Two of those rescued had sustained injuries, but these were not life-threatening.
Earlier, Defence Secretary Philip Hammond blamed militants for the deaths of hostages following reports that 11 captors and seven hostages had died in an army assault.
Speaking before Mr Hague's announcement, Mr Hammond said the deaths were "appalling and unacceptable".
"We must be clear that it is the terrorists that bear sole responsibility for it."
Labour leader Ed Miliband offered his support to the government and added: "All of my sympathy and thoughts are with those who have lost loved ones in this appalling act of terror."
Meanwhile, the family of freed hostage Darren Matthews, 29, from Teesside, have issued a statement.
It said: "We have been extremely worried about Darren and we are pleased and relieved to learn that he is safe and well. We look forward to having him home soon.
"We ask that the media respect our privacy at this difficult time."
Militants, who held the site for four days, had told a Mauritanian news agency they had seven foreign hostages.
The hostage-takers initially attacked two buses carrying foreign workers on Wednesday. A Briton and an Algerian reportedly died in that incident.
The militants then took Algerians and foreign workers hostage at the complex, which is part-operated by BP.