Prince Harry arrives at the High Court in London, June 6, 2023. (PHOTO / AP)

LONDON - Prince Harry launched a fierce attack on the "vile" press on Tuesday, blaming tabloids for destroying his adolescence and later relationships, as he gave evidence against a tabloid publisher whose titles he accuses of unlawful activities.

Harry, the fifth-in-line to the throne, became the first senior royal to appear in a witness box in more than a century in a lawsuit he and 100 others have brought against Mirror Group Newspapers (MGN).

They accuse the publisher of the Daily Mirror, Sunday Mirror and Sunday People, of widespread phone-hacking and unlawful information gathering between 1991 and 2011.

Harry said the press would try to destroy his relationships with girlfriends, blaming them for his break-up with Chelsy Davy, for causing his circle of friends to shrink, and had led to bouts of depression and paranoia

The younger son of King Charles briefly smiled as he passed the phalanx of photographers and camera crews at the High Court in central London, where he is facing hours of cross-examination from MGN's lawyer Andrew Green, over 33 newspaper articles whose details he says were obtained unlawfully.

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"Every single one of these articles played an important role, and destructive role in my growing up," he said.

Green began by personally apologizing to Harry on MGN's behalf over one instance in which it admitted unlawful information gathering.

"It should never have happened and it will not happen again," he said, adding if the court agreed MGN had committed wrongdoing on other occasions "you will be entitled to, and you will receive a more extensive apology".

In his written witness statement, Harry denounced the treatment he had experienced at the hands of the press. He said he had been labelled a "playboy prince", a "thicko", a "failure" and a "drop out".

Harry said the press would try to destroy his relationships with girlfriends, blaming them for his break-up with Chelsy Davy, for causing his circle of friends to shrink, and had led to bouts of depression and paranoia.

Britain's Prince Harry arrives at the Royal Courts Of Justice in London, March 28, 2023. (PHOTO / AP)

"Looking back on it now, such behavior on their part is utterly vile," he wrote, saying the tabloids had incited "hatred and harassment" into his and his wife Meghan's private lives.

In another section he said: "How much more blood will stain their typing fingers before someone can put a stop to this madness?

Asked by Green if he was suggesting by this that MGN journalists who wrote the articles at the center of his lawsuit had blood on their hands, Harry replied: "Some of the editors and journalists that are responsible for causing a lot of pain, upset and in some cases - perhaps inadvertently - death."

Looking serious and speaking firmly but quietly, Harry, the first senior British royal to give evidence for 130 years, said thousands if not millions of stories had been written about him, as Green pressed him on whether he had read the MGN articles in question at the time they were published.

The lawyer also sought to cast doubt on his claim the information had been unlawfully obtained and intimated that the distress he had suffered was caused by press coverage in general, not the specific MGN stories.

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Green suggested to Harry that his allegation that an article about him breaking his thumb as a teenager was the result of phone hacking, or other unlawful information gathering, was "in the realms of total speculation".

The seven-week MGN trial began last month, with Harry and the other claimants arguing hacking and unlawful information gathering was carried out with the knowledge and approval of senior editors and executives.

About 20 members of the public queued to gain access to one of the dozen or so seats allocated to the public inside the courtroom.

Harry is one of four test cases, and his specific allegations form the focus of the first three days of this week.

Mother hacked

On Monday, his lawyer David Sherborne said Harry's late mother Princess Diana, had also been a victim of hacking, and the prince referred to this in his witness statement, laying the blame at the Daily Mirror's former editor Piers Morgan.

He said the thought of Piers Morgan and his "band of journalists earwigging" into my mother's messages "makes me feel physically sick".

Morgan, now a high-profile broadcaster who works for Rupert Murdoch's News Corp, has always denied any involvement in, or knowledge of phone-hacking or other illegal activity.

"I've always heard people refer to my mother as paranoid, but she wasn't. She was fearful of what was actually happening to her and now I know that I was the same," Harry said in his statement.

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MGN, now owned by Reach, has previously admitted its titles were involved in phone-hacking, settling more than 600 claims, but Green has said there was no evidence that Harry had ever been a victim.

The publisher also argues that some of the personal information involved had come from senior royal aides, including from one of his father's former top officials.