Twitter Inc.'s /zigman2/quotes/203180645/composite TWTR +0.23% massive security breach was allegedly pulled off by a 17-year-old hacker in Florida and two others, according to officials Friday. Graham Clark of Tampa was arrested Friday and charged with 30 felony counts in a July 15 hack of Twitter's internal systems that compromised dozens of high-profile accounts ranging from the likes of Barack Obama to Elon Musk in an attempt to scam followers out of bitcoin. While the Federal Bureau of Investigation, the Department of Justice and other agencies participated in the investigation, Clark was charged by Florida State Attorney Andrew Warren in Hillsborough County because "Florida law allows minors to be charged as adults in financial fraud cases such as this when appropriate," Warren's office said in a statement. The DoJ filed three charges against Mason Sheppard, 19, from the United Kingdom, and one count against Nima Fazeli, 22, from Orlando. On Friday, Twitter said the hack occurred when company employees were fooled into granting access to systems.