Rome, Mar 12 (IANS): Italian prosecutors have launched an investigation into the deaths of eight Italian citizens who perished when an Ethiopian Airlines jet crashed shortly after take-off from Addis Ababa on Sunday, killing all 157 people on board.

The Italians who died in the crash were Sicilian regional heritage councillor and archaeologist Sebastiano Tusa, Italian NGO, the International Committee for the Development of Peoples's chief Paolo Dieci, United Nations workers Maria Pilar Buzzetti and Virginia Chimenti, and Bergamo-based charity Africa Three Thousand's President Carlo Spini, its treasurer Matteo Ravasio and Spini's wife Gabriella.

The causes of the crash, which occurred six minutes after take-off, are not yet known.

A total of UN staff, many heading for an assembly of the UN Environment Programme in Nairobi, were aboard the doomed flight.

Italian Environment Minister Sergio Costa has tweeted condolences for the victims.

"Our thoughts are with the families of the victims of the plane that came down in Ethiopia.

"Those killed included NGO volunteers who do vital work, a Sicilian regional councillor and archaeologist, aid workers and delegates to a UN environment conference where I will be heading tomorrow," he tweeted.

Passengers on the Boeing 737 Max 8 plane came from over 30 countries.