Algerian forces have moved against militants holding hostages at a gas facility in eastern Algeria, the state news agency reports.
Four foreign hostages were freed but the operation resulted in a number of “victims”, APS agency said.
Algerian soldiers had been surrounding the facility near In Amenas that kidnappers occupied on Wednesday, after killing a Briton and an Algerian.
Militants also told Mauritania’s ANI news agency that seven foreign hostages were still alive after the Algerian military raid.
Nearly 600 Algerian workers and four foreign hostages – two from Scotland, one from France and one from Kenya – were freed during the operation, APS reported.
An Irishman who had been kidnapped was freed and has spoken to his family, Ireland’s foreign ministry said.
APS quoted an unnamed source as saying that “about half” the foreign hostages had been liberated.
The Algerian military targeted two vehicles as they tried to escape from the site with an unknown number of people on board.
Algerian media reported late in the afternoon that the army operation had ended, and that Algeria’s military was in control of the gas plant, although this has not been independently confirmed.
Algerian Prime Minister Abdelmalek Sellal called UK counterpart David Cameron to say the operation was under way at 11:30 GMT, Mr Cameron’s spokesman said.
Mr Cameron made clear that he would have preferred to have been informed in advance but the Algerians said they had to act “immediately”, the spokesman added.
The White House said it was “seeking clarity” on the operation.
Militants had earlier said they were holding 41 foreign nationals. They were believed to include British, Japanese, US and Norwegian citizens.
Some 30 Algerians and 15 foreigners were reported to have escaped from the gas facility before the Algerian military intervened.
One statement purported to be from the hostage-takers called for an end to the French military intervention against rebels in neighboring Mali.
M.D