30 hostages and at least 11 Al-Qaeda linked terrorists were killed on Thursday when Algerian forces stormed a desert gas plant in a bid to free Western and local captives.

The official Algerian news agency, APS, reported on Thursday evening that the operation had ended. According to sources in Algeria, two Japanese, two Britons and a French national were among the foreign hostages killed.

Eight of the dead hostages were Algerian. The nationalities of the rest, as well as of perhaps dozens more who escaped, were unclear.

Among those captured were Americans, Norwegians, Romanians and an Austrian.

Earlier on Thursday, troops surrounded the gas facility and helicopters bombarded the terrorists and their vehicles from the air, as they tried to move their hostages.

Members of the group, an offshoot of Al Qaeda in the Islamic Maghreb (AQIM), belonged to the Khaled Aboul Abbas Brigade, led by former AQIM leader Mokhtar Belmokhtar. They seized the gas field on Wednesday and demanded the Algerian government provide them and their hostages with safe passage out of the area. Algeria refused.

The installation is jointly operated by British giant BP, the national Algerian Sonatrach oil company, and the Norwegian Statoil firm.

Some 30 Algerian workers had earlier managed to escape their captors, according to the pan-Arabic Al Jazeera news network. The British Guardian newspaper reported that an additional 25 hostages also managed to escape during the siege by Algerian forces.