A Pennsylvania man who claimed for years to have escaped from Auschwitz, met track and field star Jesse Owens and Nazi doctor Josef Mengele, confessed on Friday that he had fabricated the entire story.

“I am writing today to apologize publicly for harm caused to anyone because of my inserting myself into the descriptions of life in Auschwitz,” Joseph Hirt, 86, wrote in a letter sent to his local paper, LNP, this week. “I was not a prisoner there. I did not intend to lessen or overshadow the events which truly happened there by falsely claiming to have been personally involved.”

“I was wrong. I ask forgiveness,” he added. “I determined at that moment to do everything in my power to prevent the loss of the truth about wartime life (and death) at Auschwitz.”

For years, Hirt gave public speeches about his experiences in the second world war, including his Jewish family’s flight from Poland to Belgrade. But he also told people that he was arrested by the Nazis, sent to the concentration camp at Auschwitz, and met Mengele, the SS physician who tortured prisoners of the concentration camp. Hirt claimed to have escaped under an electric fence at the camp.

He added an extraordinary prologue and epilogue to the story, saying that he saw Adolf Hitler turn his back on Jesse Owens at the 1936 Olympics in Berlin, and that he met Eleanor Roosevelt and Owens after his arrival in the United States.

In his letter, Hirt said that he realized “it wasn’t about me”, and that he was motivated to lie by his fears that the history and horror of the camps would be forgotten. He said that he was shocked to find that Auschwitz, now a museum and memorial, had become a “clean and polished tourist destination” where visitors laughed and joked about “propaganda”.

“Flagrant denial and ignorance of the truth made me determined to keep the memories alive,” Hirt said. “I used poor judgment and faulty reasoning, risking a sullying of the truth I was trying to share.”

Hirt did not immediately reply to a request for an interview.

Earlier this year, New York history teacher Andrew Reid became suspicious of Hirt’s story and wrote a refutation of many of Hirt’s points.

The names of concentration camp victims and survivors are publicly available, and there is no record of Hirt at Auschwitz or elsewhere. Hirt admitted in his letter that he had tattooed the camp number of Auschwitz survivor Primo Levi, the acclaimed author and chemist, on his left forearm – “in no way an attempt to take on his identity, but in an effort to incorporate his symbol as a way of remembering him”.

Reid also found that Hirt’s escape story did not fit with camp records, that Mengele did not arrive at the camp until after the alleged escape, and other lies, errors and far-fetched claims in Hirt’s account. He was a six-year-old Polish boy and extraordinarily unlikely to be anywhere near Hitler at the Olympics, for instance, and Owens’ biographer found the snub was likely a fabrication, possibly conflated with another black sprinter’s story.

“I want to be clear – I am not a Holocaust denier,” Reid wrote in his own letter, noting that he got his first job from a concentration camp survivor. “It is partly in his memory and for the preservation of the truth of what millions of people endured that I have taken upon myself the task of exposing Mr Hirt’s shameful deception.”

Hirt is not the first to fabricate or exaggerate a Holocaust story, worrying historians who fear these voices encourage people who deny the deaths of six million people. Herman Rosenblat, a Polish survivor, embellished his 1993 memoir and made up some parts entirely, including the love story at its heart. At the time, historian Ken Waltzer wrote in the New Republic that he was alarmed by how quickly people accepted the story.

“This was not Holocaust education but miseducation,” he said. “This shows something about the broad unwillingness in our culture to confront the difficult knowledge of the Holocaust. All the more important then to have real memoirs that tell of real experience in the camps.”