The announcement brings to five the total number of employees lost by the state-owned oil giant in the hostage drama that began on January 16th.

"It is with deep sorrow that we have received the news today that Victor Sneberg, our country manager in Algeria, is among those who lost their lives in the terror attack at In Amenas," chief executive Helge Lund said in a statement.

Sneberg, 56, was the last of five Norwegians who were missing after the attack by Islamist militants on the gas plant, which prompted Algeria to launch a military operation on the site four days later.

The circumstances under which the five were killed remained unclear.

Algeria has said 38 workers, out of which 37 were foreign, and 29 kidnappers died in the hostage taking.