There were thirteen people in the aircraft, en route from Statoil’s Gullfaks B field to Bergen, and all of them are confirmed dead.

According to a statement by Statoil, the 11 passengers aboard the CHC-owned Eurocopter EC225LP Super Puma helicopter, were employed in Halliburton, Aker Solutions, Schlumberger, Welltec, Karsten Moholt and Statoil.

The two pilots were employed by CHC. One of the 13 is a Statoil employee, Statoil said.

Statoil also revealed the names of eight workers who have been named so far: Ole Magnar Kvamme (Statoil), Arild Fossedal and Odd Geir Turøy (Aker Solutions), Michele Vimercati (CHC), Iain Stuart, Behnam Ahmadi and Otto Mikal Vasstveit (Halliburton) and Kjetil Wathne (Karsten Moholt AS).

“Today, Statoil is a company in mourning. Yesterday, we were hit by one of the most severe accidents in the history of the Norwegian oil industry. Many families have been hit, and we have lost good colleagues and friends,” Statoil CEO Eldar Sætre, said on Saturday.

The company said it would will continue to support those who need it most, those who are directly affected, families, colleagues onshore and on the platforms.

The Accident Investigation Board in Norway will investigate the accident, and Statoil will contribute to this job, Statoil said.

The Norwegian oil company said it would also start its own investigation in cooperation with the employee representatives and the safety delegates. This investigation will be coordinated with the work of the Accident Investigation Board.

While the investigation is still ongoing, there have been reports that the helicopter’s rotor loosened and detached from the aircraft before the crash.

“Finding an answer to why the helicopter crashed is very important, both to the next of kin and to all who have the Norwegian continental shelf as their work place. The safety of everyone working for Statoil is the most important thing for us,” Sætre said.

The tragedy will be marked across Statoil Monday May 2 at 13:00 CET with a minute’s silence, and flags will be flown at half-mast all day.

The news comes as a petition to remove the Super Puma helicopter from service started by an oil worker following the crash, has now been signed by more than 10,000 people – some of them relatives killed in other incidents.

The petition calls on the CAA to “revoke the air worthiness certificates for this aircraft”, claiming that failure to do this could result in “more needless deaths”.

Commenting on the petition, the mother of 27-year-old oil rig worker Stuart Wood who died in a Super Puma crash in 2009, said all versions of the helicopter should be withdrawn.

Audrey Wood, from Newmacher, Aberdeenshire, said: “Seven years on and my life has stood still. Wouldn’t wish this heartache on my worst enemy.

“All variants of Puma should be removed from the oil industry, men should feel safe travelling to work not fear if they will ever see their loved ones at home again.”

The change.org petition says:

“This petition is for all North Sea Offshore Oil Workers and their families, and the public at large, to finally say enough is enough with the Super Puma airframe. In signing this petition you are asking for the Airbus 225 Super Puma to be permanently removed from service as its been involved in one incident too many, where yet again fatalities have occurred, and you wish to express a vote of no-confidence in the safety of this airframe. We call on the CAA to put the lives of Offshore Oil Workers and the pilots before vested interests, and revoke the airworthiness certificates for this aircraft. Failure to do this will result in more needless deaths”