germanwings plane crash alps
Rescue workers recover bodies of victims from the crash site of the Germanwings Airbus A320 Emmanuel Foudrot/Reuters

Not one body has been recovered intact from the site of the Germanwings plane crash in the French Alps, investigators revealed.

The grim detail was revealed as the search for bodies continues after the flight was crashed "on purpose" by co-pilot Andreas Lubitz last week.

The sheer ferocity of the impact has meant investigators have been forced to rely upon DNA to piece together remains.

A forensic team of 50 experts was examining around 500 body parts from the scene in a nearby town called Seynes. The difficulty of the task has been described as "unprecedented".

"We haven't found a single body intact," said Patrick Touron, deputy director of the criminal research institute.

"We have slopes of 40 to 60 degrees, falling rocks, and ground that tends to crumble," he told reporters.

"Some things have to be done by abseiling. Since safety is key, the recovery process is a bit slow, which is a great regret."

DNA from a total of 78 victims has been recovered so far, meaning the bodies of nearly half of all passengers on board remain missing.

Meanwhile, Relatives of the 149 innocent people on board the Germanwings Airbus A320 continue to wait for updates, while more details emerge about crazed co-pilot Andreas Lubitz.

One of the plane's two black box recorders - vital in establishing precisely what happened on board the doomed flight - remains missing.

Audio from the recovered recorder contains the harrowing sound of passengers screaming as they career toward a mountain and also metallic scrapping noises as a wing hits rocks.