A 21-year-old man has been sentenced to 10 years in prison after becoming one of the first people in the United States to be convicted of stealing cryptocurrency by hacking into cell phones. Prosecutors in Santa Clara announced the jail sentence on April 22.

In February, Joel Ortiz had pleaded guilty and to theft and accepted the 10-year plea deal.

Ortiz stole more than $7.5 million from at least 40 victims: the press release notes that he then spent $10,000 a time at Los Angeles nightclubs, hired a helicopter to fly him and his friends to a music festival, and bought top-end Gucci clothes and luggage.

In May 2018, one cryptocurrency entrepreneur in Cupertino lost $5.2 million in a matter of minutes, prosecutors note.

Prosecutors described the one-time high school valedictorian as a “prolific SIM swapper who targeted victims to steal cryptocurrency and to take over social media accounts with the goal of selling them for bitcoin (BTC).”

Illegal SIM swaps often involve duping phone companies into switching cell phone numbers to a new SIM card by providing stolen addresses and social security numbers. From here, hackers can circumvent two-step authentication measures that are designed to keep crypto safe.

Ortiz was detained at the Los Angeles International Airport last year, and investigators say they have only been able to recover $400,000 of the stolen funds. They believe the rest has either been hidden or spent. Prosecutor Erin West said:

“These are not Robin Hoods. These are crooks who use a computer instead of a gun. They are not just stealing some ethereal, experimental currency. They are stealing college funds, home mortgages, people’s financial lives.”

Oritz had been sentenced on April 19 by a judge after two hearings where victims described the financial devastation caused by his crimes.

In February in a separate case, an individual was indicted in New York for stealing identities and funds, including crypto, in the state’s first SIM swapping prosecution.