Islamist militants in Algeria captured dozens of foreign workers near a gas field in eastern Algeria on Wednesday.
British Petroleum, which runs the facility along with Algerian state-owned Sonatarch and Norwegian energy firm Statoil, released a statement on Thursday, saying:
BP has confirmed the current status of all its staff who were at In Amenas at the time of the attack. A number of BP staff are among those held on the site. To ensure we do not risk compromising the safety of these staff in any way, we do not currently intend to publicly release details of our staff members; their number, nationalities or identities. The safety of these staff, and of all others being held, is our top priority.
A later update from the company said:
Sadly, there have been some reports of casualties but we are still lacking any confirmed or reliable information. There are also reports of hostages being released or escaping.
The kidnappers, believed to be Al Qaeda-linked militants, claimed they held as many as 41 hostages, while Statoil confirmed that 12 of its Norwegian employees were captured, according to UPI.
UPI noted that while a number of Westerners are among the hostages, the governments involved have kept details sparse out of safety concerns.
Early on Wednesday, a British national was reported killed at the gas field in Algeria, while other Britons and an Irishman were reported captured.
The New York Times said workers from the US, France, Britain, Japan and Norway were among the hostages, citing officials.
A statement from a group called Al Mulathameen claimed that it was holding "seven Americans, two French, two British as well as other citizens of various European nationalities.
An operation by the Algerian military on Thursday resulted in high casualties and many rescues, according to the BBC, which cited the Algerian state news agency APS.
Reports that quoted the militants said 34 hostages and 14 kidnappers had died in the military's assault on Thursday. APS reported that nearly 600 Algerian workers and four foreign hostages (two Scottish, one French and one Kenyan) were freed.
Ireland's Foreign Affairs Department said an Irishman who was among the group of hostages was freed and safe.
"He has been in touch with his family. We understand that he is safe and well. He is no longer a hostage," a ministry spokesman told Reuters.
The leaders of the countries involved in the hostage crisis seem to be equally in the dark about the situation on the ground.
UK Prime Minister David Cameron told his Algerian counterpart that he was "extremely concerned" about the "very grave and dangerous situation," according to a spokesman for Cameron, cited by Reuters.
Cameron was not given prior notice of plans for the Algerian operation, and would have preferred to have been informed, the spokesman said.
A spokesman for the Norwegian Foreign Ministry told the BBC, "We have no confirmed information to share with you at this stage." He added, "We're sending a team to Algeria including members of the Foreign Ministry, health personnel, police officers and so on. The Norwegian prime minister spoke to his Algerian counterpart and was informed of the action."
Meanwhile, Japan confirmed that several Japanese employees of the engineering company JCG Corp. were among the hostages, according to The Japan Times.
Chief Cabinet Secretary Yoshihide Suga said the Japanese government had not yet formed a full picture of what happened. He said Tokyo has arranged to hold teleconferences with foreign ministers of other countries whose citizens have been captured, including Britain, France and Norway.
According to Agence France Presse, Japanese Prime Minister Shinzo Abe called on his Algerian counterpart to halt the military operation, and place the highest priority on people's lives. "[Abe] urged him to halt such actions," Suga told reporters.
French President Francois Hollande, who has been in touch with the White House and with the UK, said the hostage crisis was unfolding in "dramatic conditions," according to the BBC. He also added that the situation in Algeria justified France's military intervention in Mali.
"This is an ongoing situation and we are seeking clarity," said White House Spokesman Jay Carney. He added that President Barack Obama is being briefed regularly by his national security team, according to Al Arabiya.
CBS News reported on Wednesday that at least three Americans were thought to be among the hostages, citing anonymous sources. US Defense Secretary Leon Panetta said, "It is a very serious matter when Americans are taken hostage along with others."
The US government, like the other governments involved, has not released any names or numbers of its nationals taken hostage.
This is a developing story. Please check GlobalPost's live blog on the situation for the latest updates.