In a statement BP said the site was “attacked and occupied by a group of unidentified armed people,” and some of its personnel are believed to be “held by the occupiers.”

The number and identities of the hostages was still unclear, but Ireland announced that a 36-year-old married Irish man was among them, while Japan and Britain said their citizens were involved as well. A Norwegian woman said her husband called her saying he had been taken hostage…

A group called the Katibat Moulathamine, or the Masked Brigade, called a Mauritanian news outlet to say one of its affiliates had carried out the operation on the Ain Amenas gas field, taking 41 hostages from nine or 10 different nationalities, including the seven Americans.