A British man pleaded guilty Tuesday for his role in schemes to hack the Twitter accounts of celebrities like former US President Barack Obama and Twitter CEO Elon Musk and stealing $794,000 in cryptocurrency.

Joseph James O'Connor, 23, pleaded guilty in a New York court after being extradited from Spain on April 26.

He was arrested nearly two years ago in Spain for the July 2020 hack of over 130 Twitter accounts, including those of Apple, Uber, American singer Kanye West, Microsoft co-founder Bill Gates, and US President Joe Biden.

O'Connor and others in his hacking group hijacked the accounts and asked the owners' followers to send them bitcoin, promising to double their money.

In 2019, the group also used a technique known as sim card swaps to break their way into social media accounts of two media stars, not named in court filings but named in press reports as TikTok star Addison Rae and actress Bella Thorne.

The group threatened to release their private images and other information.

In addition, they used the same technique to steal $794,000 of virtual currency from a New York cryptocurrency company.

O'Connor, who went by the online name of PlugwalkJoe, pleaded guilty to multiple counts of computer intrusion, extortion, stalking, wire fraud, and money laundering.

The most serious of the charges brings up to 20 years in prison.

"O’Connor’s criminal activities were flagrant and malicious, and his conduct impacted multiple people’s lives. He harassed, threatened, and extorted his victims, causing substantial emotional harm," indicated Kenneth A Polite Jr, an assistant attorney general in the US Justice Department’s criminal division.

In July 2021, Florida teenager Graham Ivan Clark, the alleged mastermind of the hacking group, was sentenced to three years in juvenile prison under a plea agreement.

Clark, only 17 when he was charged, was sentenced to the maximum allowed under Florida’s Youthful Offender Act.

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