Eurocopter CEO Guillaume Faury speaks to Rebecca Curran, following the decision to lift the suspension of all Super Puma flights in the UK North Sea

Helicopter bosses say all the indications show the helicopter crash off Shetland was not the result of a mechanical failure.

Four people died after the L2 aircraft went down in the water a few miles from Sumburgh airport.

Helicopter Manufaturer Eurocopter say the accident could be as a result of a number of factors - including environment, maintenence or human error.

It comes as the suspension on Super Puma flights to and from the UK North Sea is lifted.

But the Air Accident Investigaton Branch say it's too early to know the cause, and only recovered the black box recorder this evening.

Eurocopter is helping the AAIB with the investigation.