A best-selling Holocaust memoir has been revealed to be a fake. The author was never trapped in the Warsaw ghetto. Neither was she adopted by wolves who protected her from the Nazis, nor did she trek 1,900 miles across Europe in search of her deported parents or kill a German soldier in self-defense. She wasn’t even Jewish, The Associated Press reported. Misha Defonseca, 71, right, a Belgian writer living in Dudley, Mass., about 60 miles southwest of Boston, admitted through her lawyers last week that her book, “Misha: A Mémoire of the Holocaust Years,” translated into 18 language and adapted for the French feature film “Surviving With Wolves,” was a fantasy. In a statement to The Associated Press, Ms. Defonseca said: “The story is mine. It is not actually reality, but my reality, my way of surviving. I ask forgiveness to all who felt betrayed. I beg you to put yourself in my place, of a 4-year-old girl who was very lost.” Ms. Defonseca, who gave her real name as Monique De Wael, said her parents were arrested and killed by Nazis for Belgian resistance activities when she was 4; she was cared for by her grandfather and uncle. She came under pressure to defend her book after Sharon Sergeant, a genealogical researcher in Waltham, Mass., said she had found clues in the unpublished United States version of the book.

In “Love and Consequences,” a critically acclaimed memoir published last week, Margaret B. Jones wrote about her life as a half-white, half-Native American girl growing up in South-Central Los Angeles as a foster child among gang-bangers, running drugs for the Bloods.

The problem is that none of it is true.

Margaret B. Jones is a pseudonym for Margaret Seltzer, who is all white and grew up in the well-to-do Sherman Oaks section of Los Angeles, in the San Fernando Valley, with her biological family. She graduated from the Campbell Hall School, a private Episcopal day school in the North Hollywood neighborhood. She has never lived with a foster family, nor did she run drugs for any gang members. Nor did she graduate from the University of Oregon, as she had claimed.

Riverhead Books, the unit of Penguin Group USA that published “Love and Consequences,” is recalling all copies of the book and has canceled Ms. Seltzer’s book tour, which was scheduled to start on Monday in Eugene, Ore., where she currently lives.

In a sometimes tearful, often contrite telephone interview from her home on Monday, Ms. Seltzer, 33, who is known as Peggy, admitted that the personal story she told in the book was entirely fabricated. She insisted, though, that many of the details in the book were based on the experiences of close friends she had met over the years while working to reduce gang violence in Los Angeles.

“For whatever reason, I was really torn and I thought it was my opportunity to put a voice to people who people don’t listen to,” Ms. Seltzer said. “I was in a position where at one point people said you should speak for us because nobody else is going to let us in to talk. Maybe it’s an ego thing — I don’t know. I just felt that there was good that I could do and there was no other way that someone would listen to it.”

The revelations of Ms. Seltzer’s mendacity came in the wake of the news last week that a Holocaust memoir, “Misha: A Mémoire of the Holocaust Years” by Misha Defonseca, was a fake, and perhaps more notoriously, two years ago James Frey, the author of a best-selling memoir, “A Million Little Pieces,” admitted that he had made up or exaggerated details in his account of his drug addiction and recovery.

Ms. Seltzer’s story started unraveling last Thursday after she was profiled in the House & Home section of The New York Times. The article appeared alongside a photograph of Ms. Seltzer and her 8-year-old daughter, Rya. Ms. Seltzer’s older sister, Cyndi Hoffman, saw the article and called Riverhead to tell editors that Ms. Seltzer’s story was untrue.

“Love and Consequences” immediately hit a note with many reviewers. Writing in The Times, Michiko Kakutani praised the “humane and deeply affecting memoir,” but noted that some of the scenes “can feel self-consciously novelistic at times.” In Entertainment Weekly, Vanessa Juarez wrote that “readers may wonder if Jones embellishes the dialogue” but went on to extol the “powerful story of resilience and unconditional love.”

In the vividly told book, Ms. Seltzer wrote about her African-American foster brothers, Terrell and Taye, who joined the Bloods gang when they were 11 and 13. She chronicled her experiences making drug deliveries for gang leaders at age 13 and how she was given her first gun as a birthday present when she was 14. Ms. Seltzer told The Times last week, “One of the first things I did once I started making drug money was to buy a burial plot.”

Sarah McGrath, the editor at Riverhead who worked with Ms. Seltzer for three years on the book, said she was stunned to discover that the author had lied.

“It’s very upsetting to us because we spent so much time with this person and we felt such sympathy for her and she would talk about how she didn’t have any money or any heat and we completely bought into that and thought we were doing something good by bringing her story to light,” Ms. McGrath said.

“There’s a huge personal betrayal here as well as a professional one,” she said.

Ms. Seltzer said she had been writing about her friends’ experiences for years in creative-writing classes and on her own before a professor asked her to speak with Inga Muscio, an author who was then working on a book about racism. Ms. Seltzer talked about what she portrayed as her experiences and Ms. Muscio used some of those accounts in her book. Ms. Muscio then referred Ms. Seltzer to her agent, Faye Bender, who read some pages that Ms. Seltzer had written and encouraged the young author to write more.

In April 2005, Ms. Bender submitted about 100 pages to four publishers. Ms. McGrath, then at Scribner, a unit of Simon & Schuster, agreed to a deal for what she said was less than $100,000. When Ms. McGrath moved to Riverhead in 2006, she moved Ms. Seltzer’s contract.

Over the course of three years, Ms. McGrath, who is the daughter of Charles McGrath, a writer at large at The Times, worked closely with Ms. Seltzer on the book. “I’ve been talking to her on the phone and getting e-mails from her for three years and her story never has changed,” Ms. McGrath said. “All the details have been the same. There never have been any cracks.”

In a telephone interview, Ms. Seltzer’s sister, Ms. Hoffman, 47, said: “It could have and should have been stopped before now.” Referring to the publisher, she added: “I don’t know how they do business, but I would think that protocol would have them doing fact-checking.”

Ms. Seltzer said she had met some gang members during a short stint she said she spent at “Grant” high school “in the Valley.” (A Google search identifies Ulysses S. Grant High School, a school on 34 acres in the Valley Glen neighborhood in the east-central San Fernando Valley.) “It opened my mind to the fact that not everybody is as they are portrayed on the news,” she said. “Everything’s not that black and white or gray or brown.”

She said that although she returned to Campbell Hall, she remained in touch with people she met at Grant and then began working with groups that were trying to stop gang violence. She said that even after she moved to Oregon, she would often venture to South-Central Los Angeles to spend time with friends in the gang world.

In the book, she describes her foster mother, Big Mom, an African-American woman who raised four grandchildren and a foster brother, Terrell, who was gunned down by Crips right outside her foster mother’s home.

Ms. Seltzer, who writes in an author’s note to the book that she “combined characters and changed names, dates, and places,” said in an interview that these characters and incidents were in part based on friends’ experiences. “I had a couple of friends who had moms who were like my mom and that’s where Big Mom comes from — from being in the house all the time and watching what goes on. One of my best friend’s little brother was killed two years ago, shot,” she said.

Ms. Seltzer added that she wrote the book “sitting at the Starbucks” in South-Central, where “I would talk to kids who were Black Panthers and kids who were gang members and kids who were not.”

“I’m not saying like I did it right,” Ms. Seltzer said. “I did not do it right. I thought I had an opportunity to make people understand the conditions that people live in and the reasons people make the choices from the choices they don’t have.” Ms. McGrath said that she had numerous conversations with Ms. Seltzer about being truthful. “She seems to be very, very naïve,” Ms. McGrath said. “There was a way to do this book honestly and have it be just as compelling.”