A 19-year-old British citizen, Mason Sheppard, living in Bognor Regis is one of three individuals charged over a major Twitter hack, according to the US Department of Justice.
Californian authorities filed felony charges against the teenager.
The UK’s National Crime Agency (NCA) confirmed it had searched a property in Bognor Regis with police on Friday.
A teenager in Tampa and Nima Fazeli, 22, of Orlando, were also charged in Florida.
US Attorney David L Anderson said the arrests proved “nefarious hacking… for fun or profit” did not pay off.
Twitter accounts of multiple high-profile US figures were hijacked in an apparent Bitcoin scam on 15 July.
They included former President Barack Obama, Amazon boss Jeff Bezos, entrepreneur Elon Musk, Microsoft founder Bill Gates, Democratic presidential hopeful Joe Biden and reality star Kim Kardashian West, who all falsely tweeted out requests for Bitcoin donations.
In his statement, US Attorney Anderson said: “There is a false belief within the criminal hacker community that attacks like the Twitter hack can be perpetrated anonymously and without consequence.”
He added: “Criminal conduct over the Internet may feel stealthy to the people who perpetrate it, but there is nothing stealthy about it. In particular, I want to say to would-be offenders, break the law, and we will find you.”