It emerged last year that Hari had inserted quotes not given to him directly into a related interview.

He also edited Wikipedia entries under another username, admitting in his apology in the Independent that they were sometimes made in a “juvenile or malicious” way.

Today at the Leveson inquiry into press standards, the Independent’s editor, Chris Blackhurst, said the revelations caused “enormous shock, to myself as somebody who prior to then had mainly been an observer and admirer of Johann’s journalism, but much deeper shock to his colleagues at the Independent. It was really profound and totally unexpected.”

He also admitted that the scandal had “severely damaged” the paper.

He denied that it was a cover up, saying that the company and his colleagues had no idea what he was doing.

He added: “I am surprised you say cover-up in the sense we had inklings because that is genuinely news to me. We had no inklings of the plagiarism. One of the problems was no one had ever complained; no journalist, no person he interviewed, no reader, no colleagues, nobody had alerted us.”

He said the evidence was not sufficient to sack Hari, who has taken ethics training in New York and spent four months without pay.

Blackhurst also said Hari “won’t be interviewing people” and that “everything he writes will be heavily looked at”.

Hari was also previously accused of plagiarism by Private Eye in 2003, but others began to complain after investigative work by the Deterritorial Support Grouppppp and Brian Whelan were picked up by mainstream newspapers.

Hari admitted that he had quoted people that he interviewed “as they expressed [their thoughts] in writing, rather than how they expressed it in speech”.

Blackhurst insisted Hari hadn’t invented facts for hard news stories and said he had learned his lesson.