Mauritanian news agency ANI writes those holding the hostages claim they repelled soldiers' bid, with a source within the al-Qaida-affiliated group that has claimed responsibility for the kidnappings alleging there was an exchange of fire.

The same individual also asserted Algerian army soldiers were forced to retreat, as well as that the alleged dozens of hostage-takers are armed with weapons including anti-aircraft missiles and mortars.

Norwegian Prime Minister Jens Stoltenberg confirmed at a press conference at 7pm today that Norwegians were amongst those who had been taken hostage at a Statoil plant in Algeria.

The attack appears to have been carried out by militant Islamists on Tuesday night. The plant lies on an inaccessible area near the Libyan border. There has been speculation in the foreign media that the action may be a response to French actions in Mali.

“I can confirm that 13 Norwegians are involved, said Stoltenberg. “Two of the 17 employees at the Statoil plant have come to harm.” He could not however give details of how many Norwegian employees were being held as hostages.

Statoil's Lars Christian Bacher tells NRK nine of their staff is being held.

British news sources however claim that two people have been killed. The British Foreign Office confirmed that several British nationals were caught up in the attack on a gas field which is jointly owned by BP and Statoil.

News agency AFP reports one British and one French national were killed in the attack, as well as an Algerian security guard.

It is unclear at this stage how many workers have been kidnapped. Nationals from Japan and Ireland are also known to be amongst the hostages. The kidnappers themselves claim they are holding 41 people.

Algerian newspaper Les Dernières Nouvelles reports that the attackers are still in the oil-workers’ accommodation area and that they are heavily armed. They are surrounded by the Algerian national army, and have reportedly threatened to blow up the entire plant if the army takes action against them - having laid mines around the base where the hostages are being held.

Stoltenberg also confirmed that a Norwegian emergency team is being sent to the area.

“We were informed this morning, and since then have been working to secure the hostages and take care of their loved ones. This is now in full swing. We have also sent an emergency team to aid the embassy in Algeria. At the moment we can’t talk about other measures we have set in train,” he told reporters.

“Several countries are affected. We are in contact with foreign leaders to coordinate the major rescue action that is now underway. Norway is taking this situation very seriously. We do not wish to speculate who is behind it. Our job this evening is to get our fellow countrymen home.”

Norway's Ministry of Foreign Affairs updated travel advice to Algeria earlier today, advising "against travel to or staying in Algeria."

"Norwegian citizens residing in or planning to travel to Algeria, are requested to contact the embassy in Algiers for updated information," officials said in a statement.

Statoil encourages affected persons to get in touch on (+47) 800 83 003.

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