His reporting won him numerous awards including CNN's "Journalist of the Year" in 2014, the European Press Prize in 2017 and Germany's "Reporter of the Year" in 2013, 2015, 2016 and earlier this month.
Several major features nominated or winning awards are among the articles in question, including "Number 440", about prisoners at Guantanamo Bay that was named Deutscher Reporterpreis story of the year in 2016. Relotius worked as a freelancer for years, writing for several outlets in Germany and overseas.
Almost everything else, including a coal plant employee named Neil Becker, who doesn't actually exist, or quotes from a restaurant employee, who was falsely called the owner of a restaurant and whose son was given a fictional illness, was made up.
The news outlet apologised to its readers for the deceit and described it as "a low point in Spiegel's 70-year history".
Spiegel said on Wednesday that it would call on a commission to investigate the case and prevent repeats, but that "even with the best intentions they can't be entirely ruled out". The magazine said it has published nearly 60 articles by Relotius, who wrote his first article for the publication as a freelancer in 2011.
"I am sick and I need to get help", he was quoted as saying by The Guardian.
The article's co-author, Juan Moreno, grew suspicious and collected evidence against Relotius during a subsequent trip to America on another story.
Miss Philippines Catriona Gray Crowned Miss Universe 2018
Without hesitation, the Australian-Filipina beauty said: "I'm for being used in medical use but not so for recreational use". She won the right to represent her country at the Miss Universe pageant in Athens, Greece shortly afterwards.
"The management of Der Spiegel will appoint a committee of internal and external experts", the publication said, adding that the results will be published.
Moreno raised the alarm at Der Spiegel and used another reporting trip to the U.S. to track down some of the people quoted in the article to find out they had never met Relotius.
"It wasn't because of the next big thing". During his time as a freelance journalist, his work got published by other media including Cicero, the Neue Zürcher Zeitung am Sonntag, the Financial Times Deutschland, Die Tageszeitung, Die Welt, Süddeutsche Zeitung Magazin, Weltwoche, Zeit Online and the Frankfurter Allgemeine Sonntagszeitung.
German publication Der Spiegel revealed Wednesday that it discovered one of its star journalists had been fabricating stories for years. Some of the reports, they found, were nothing more than "concocted bunk". Claas Relotius paints pictures in the reader's mind that unfold like a film, ' said Franz Fischlin, chairman of the judging panel.
Relotius told Spiegel he regretted his actions and was deeply ashamed, the magazine said.
Anderson and Jake Krohn, who co-authored the Medium piece, are receiving global praise for their rebuttal article exposing the fraudulent Der Spiegel story.