EFE | Seyne-les-Alpes, France

French investigators are making progress with their analysis of the human remains found at the site of the Germanwings passenger jet crash in the French Alps and on Sunday said that they have already performed DNA tests on the remains of 78 people.

That is more than half the 150 people who were on board the plane, although the names of those tested have not yet been released, since to determine that it will be necessary to crosscheck the results obtained at the field laboratory in Seyne-les-Alpes, France, with the DNA samples provided by the victims' relatives and being held in Paris.

Search works to collect debris and find the second black box resume at the crash site of the Germanwings Airbus A320 in the French Alps, above the tow
Search works to collect debris and find the second black box resume at the crash site of the Germanwings Airbus A320 in the French Alps, above the town of Seyne-les-Alpes, southeastern France, 29 March 2015. EFE/EPA

The collection of remains continues with about 50 helicopter flights over the very rough crash site terrain and about 50 people combing the area for body parts, the victims' possessions and key pieces of plane debris.

So far, the site has been accessible only by air, but Marseille prosecutor Brice Robin, who is in charge of the investigation, said that a road will be opened up to the area so that vehicles can get in and out, a move that will serve to accelerate the effort.

Investigators say that the recovery of remains will not be finished for another 10 days and it will require more time to identify those remains.

Only when the laborious process is finished will the remains be handed over to the victims' relative. It is very possible that investigatory authorities will order additional analyses of the remains of the pilot and copilot, as per regular protocol in any kind of air accident.

Special attention is being paid by those searching the crash site for the plane's second black box, which despite six days of intensive effort has not turned up.

Investigators say, however, that the violence of the crash at 700 kph (about 435 mph) into a ravine-covered and rocky mountainside is making the flight data recorder hard to find, but they are confident that they will uncover it sooner or later.

From the analysis of the cockpit voice recorder, which was found quickly among the plane's debris, investigators say that German copilot Andreas Lubitz intentionally crashed the plane, killing all aboard.

The Airbus belonging to Germanwings was en route from Barcelona to Düsseldorf, Germany, when Lubitz locked the pilot out of the cockpit and caused the plane to descend slowly but surely into the mountainside. Most of the people on board were Spaniards and Germans.

According to the French daily Le Parisien, Lubitz was suffering from generalized anxiety disorder for which his doctors had prescribed "medicines for the treatment of psychological illness."