In this photo taken on Monday, Jan. 20, 2020, Yevgeny Kovalev, one of the Auschwitz concentration camp's survivors, shows the camp's identification number tattooed on his arm, during an interview with the Associated Press at his flat in Moscow, Russia. Kovalev was arrested by the Nazis as a teenager and sent to the Auschwitz death camp is still amazed 75 years later that he survived the ordeal. The 92-year-old was speaking ahead of the 75th anniversary on Monday, Jan. 27, 2020 of the camp's liberation in 1945. (AP Photo/Alexander Zemlianichenko)

MOSCOW (AP) — The 75 years since Yevgeny Kovalev was a teenage prisoner in Auschwitz have been marked by tormented memories and a wonder that he’s still alive.

“Remembering all that is always like torture for me, can you imagine that? I’m even wondering myself how I could survive those times,” the 92-year-old retired Russian factory worker told The Associated Press ahead of the 75th anniversary Monday of the liberation of Auschwitz by the Red Army.

“We lived for minutes. We didn’t hope that we would survive,” he said.

Kovalev’s journey into the depths of the Nazi death-camp system began when he was arrested in 1943 at age 15 for helping partisans fight German forces occupying the Smolensk area in western Russia.

He aided in sabotage attacks that blew up Nazi Germany’s trains and equipment.

“They put me on a bench, tied up my feet and body and scourged me with whipping sticks. My shirt was wet through with blood,” he said.

He was sent to Auschwitz-Birkenau, the vast expanse of crude barracks and crematoria built by the Nazis in occupied Poland that was created to supplement the original Auschwitz camp, where the first victims to be fatally gassed and incinerated by the Nazis were Soviet war prisoners.

Auschwitz was the most notorious in a system of death and concentration camps that Nazi Germany operated on territory it occupied across Europe. In all, 1.1 million people were killed there, most of them Jews from across the continent.

At Birkenau, trains pulling boxcars crammed with prisoners pulled into the camp and the occupants were unloaded onto the platform.

“Those people were civilians. None of them knew they would be burned,” he recalled. “They went to decontamination, went into the wash house, were locked inside and Zyklon the gas came. In five to seven minutes, everyone was dead.”

Many of the arrivals were told they were being taken to showers for decontamination.

So many prisoners were killed that the crematoria on the edge of the camp couldn’t incinerate all the bodies. Auschwitz’s Sonderkommando prisoner work units threw many bodies into open pits and burned them there.

The crematoria worked around the clock. “Smoke came day and night and the smell was terrible,” he said.