Polish President Bronislaw Komorowski lays a wreath at the Executions Wall, or Wall of Death, of the Auschwitz Nazi death camp in Oswiecim, Poland, on Jan. 27. (Czarek Sokolowski/AP)

When the Soviet Army's 322nd Rifle Division entered the concentration camp at Auschwitz on Jan. 27, 1945, they found a desolation. Mounted on shaggy ponies, they had proceeded with caution as they entered the camp, fearful of a Nazi ambush. But there was no trace of the German enemy.

Eventually, Ivan Martynushkin, then a 21-year-old lieutenant, and his comrades spotted "some people behind barbed wire." The Nazis had evacuated the facility in Poland, the site of one of the world's most horrific slaughters. But some 7,000 of the weakest and most infirm inmates remained. The Soviet soldiers also came across more than 600 moldering corpses.

"It was hard to watch them. I remember their faces, especially their eyes which betrayed their ordeal," Martynushkin told Agence France Presse this week, ahead of the 70th anniversary of Auschwitz's liberation. Martynushkin is one of the few surviving Soviet soldiers from that day, and has spoken on numerous occasions about his experience then.

"At first there was wariness, on both our part and theirs," he said in an interview with Radio Free Europe. "But then they apparently figured out who we were and began to welcome us, to signal that they knew who we were and that we shouldn't be afraid of them — that there were no guards or Germans behind the barbed wire. Only prisoners."

There was a grim sense of relief. "We saw emaciated, tortured, impoverished people," Martynushkin told CNN five years ago. "Those were the people I first encountered. ... We could tell from their eyes that they were happy to be saved from this hell. Happy that now they weren't threatened by death in a crematorium. Happy to be freed. And we had the feeling of doing a good deed — liberating these people from this hell."

Between 1941 and 1945, the Nazis killed at least 1.1 million people in Auschwitz's gas chambers and execution grounds — the vast majority of them  were Jews, but the victims also included Poles, Roma, homosexuals and Soviet prisoners of war. Ten days prior to the arrival of the Soviet Army, which had been sweeping through Nazi-held territory in Poland, retreating Nazi troops abandoned Auschwitz and forced some 60,000 inmates on a "death march" away from the site.

The Nazis had attempted to destroy parts of the camp, but could not erase all evidence of the genocide they had perpetrated. At Auschwitz, Martynushkin and his unit found some 370,000 men's suits, 837,000 women's garments, and 7.7 tons of human hair, reports AFP.

Soviet propaganda at the time did not single out the brutal nature of the Holocaust. Rather, the discovery of these camps seemed to Martynushkin and others to be in keeping with the wider ravages of the Nazi war effort in what's now Eastern Europe and parts of Russia.

"I had seen towns destroyed," said Martynushkin, in an interview with the Daily Mail five years ago. "I had seen the destruction of villages. I had seen the suffering of our own people. I had seen small children maimed. There was not one village which had not experienced this horror, this tragedy, these sufferings."

Before they found Auschwitz, he recalls, Martynushkin and his comrades "knew nothing" of the Nazis' "Final Solution."

In the decades since, he has attended various commemorative events and was awarded an honorary medal at a ceremony in the Polish city of Krakow in 2005. But this year's ceremony was marred by contemporary politics.

The souring of ties over the past year between Moscow and Europe, including the Polish government, led to Russian President Vladimir Putin's absence at Tuesday's official commemoration.

"I thought that the date associated with the liberation of Auschwitz, these historic events, might deserve the same kind of public unity," Martynushkin lamented to Radio Free Europe.

"In spite of all the strife and all the different approaches to things going on in the world, we should have been able to come together and pay proper tribute to those events and those people who died. But unfortunately, that didn't happen," he said.