Moscow: Russian investigators detained four more staff members on Thursday at the Moscow airport where the CEO of French oil giant Total died when his plane collided with a snow plough.
Those detained include an intern air traffic controller, her supervisor, who was in charge of flights at the time, and the heads of the airport's air traffic controllers and runway cleaners.
Investigators had already detained the driver of the snow plough and a court hearing on Thursday was expected to sanction his arrest.
Investigators named the detained intern as Svetlana Krivsun. Russian media had reported earlier that the controller in charge of Christophe de Margerie's plane was a trainee.
"The investigation suggests that these people did not respect the norms of flight security and ground operations, which led to the tragedy," the powerful Investigative Committee in charge of the probe said.
At the same time the Vnukovo airport announced the resignations of its general director and his deputy "due to the tragic event" after the management was accused of "criminal negligence" by investigators.
Neither of the two airport directors who resigned was detained by investigators, however.
Total on Wednesday named new bosses after an emergency meeting in Paris, bringing back Thierry Desmarest who was both chairman and chief executive at Total from 1995 to 2007 -- as chairman of the group.
Philippe Pouyanne, who currently heads the refining and chemicals division, was named as chief executive.
In Moscow, French investigators joined a local team to probe the accident, which Russian experts said was caused by criminal negligence on the part of senior airport officials.
Three crew members were killed along with De Margerie.
Investigators began analysing the jet's black boxes, which record the flight history and conversations in the cockpit.
Snowplough driver Vladimir Martynenko, accused by investigators of having been drunk on the job, arrived at a Moscow district court today for a hearing to decide whether to formally arrest him on the request of investigators.
Martynenko told investigators in footage aired on Russian television that he had got lost.
"When I lost my bearings, I myself didn't notice when I drove onto the runway," the 60-year-old said.