Corpses at Dachau (file)
Corpses at Dachau (file) Flash 90

French former World War II deportee Clement Quentin had lost all hope and was simply "waiting to die" when US forces liberated the Nazi death camp of Dachau on April 29, 1945.

Seventy years on, the 94-year-old emotionally recalls American trucks rolling into the southern German camp to cries of joy amid the unspeakable horror.

When the US soldiers arrived "we were no longer normal human beings, we weren't yet animals, but only just," the former resistance member, who spent 10 months at Dachau, told AFP.

Despite his fragile state of health, Quentin will travel to the former death camp with his son on Sunday, for ceremonies to mark the 70th anniversary of the camp's liberation that German Chancellor Angela Merkel will also attend.

It is not his first trip back to the place where he thought he would end his days but will again revive memories of the scenes that awaited the liberating forces - the gas chambers, the piled-up corpses, the stench of death.

"I was interned in block 5, the one for the disabled, I was waiting to die," Quentin, who lives in western France, said in a telephone interview.

"I weighed about 30 kilos (66 pounds). Sometimes we used to eat from our bowls where we defecated. There was no hygiene, they let us die because we were no longer useful."

His recollection of the day they were freed also remains very clear.

"Towards 4 in the afternoon, we heard cheers and shouting and we saw soldiers pass in front of our block," he said. "They had destroyed the fence."

Sick and half-starved, Quentin, who was only 24 at the time, managed to haul himself outside of his barracks.

"I saw a crowd at the first watchtower. I saw that someone was hitting other people with a stick," he said. "I learnt later it was the SS who were in the watchtowers and who were beaten by the prisoners."

"What have they done to you?"

That evening of April 29, 1945, while wandering through the camp barracks where thousands of Jewish, communist, gay and political prisoners were held, Quentin, by chance, came across his Resistance commander.

"Ernest, Ernest," he remembered calling out, but his friend responded awkwardly: "who are you? I don't know you."

"It's me, Clement Quentin," he replied.

"But I don't recognize you. What have they done to you? What have they done to you?" his friend asked.

The SS had subjected him to medical experiments, with the camp's doctors infecting him with tuberculosis.

"I served as a human guinea pig. I thought I'd die in the following days or months," he said. "And we were liberated."

Once freed, Quentin was initially looked after by a herbalist, who sent former prisoners to collect plants growing in the fields of the green and rural state of Bavaria, where Dachau is located.

He was evacuated from the camp in June by an American convoy and taken back to France, where spent 11 months in care.

Twenty years later, he returned to Dachau for the first time with his wife and children but wasn't allowed to enter the camp, which had not yet become a public memorial.

Then, silence. For 30 years, he did not talk about his Dachau ordeal, but at night he relived the horror.

"Scratch marks from my nails were on the wall above my bed," he said. "It took me 28 years to put myself back together again."

Since then he has regularly made the trip to the camp memorial site for commemorations.

Dachau was opened in 1933, less than two months after genocidal Nazi leader Adolf Hitler became German chancellor, to house political prisoners.

More than 200,000 Jews, gays, Roma, political opponents, disabled people and prisoners of war were imprisoned at the camp.

Over 41,000 people were killed, starved or died of disease before the US troops liberated it.

"Every time I pass by block 5 where I was held, I cry," Quentin said, his voice choking up.