Two Massachusetts men have been arrested for using “SIM swapping” attacks to help them steal cryptocurrencies from victims and take over access to social media accounts.

On Thursday, federal agents arrested(Opens in a new window) 21-year-old Eric Meiggs and 20-year-old Declan Harrington for the suspected crimes, which involved duping cellular providers into handing over access to victims’ mobile phone numbers.

Getting access to the numbers opened the door for Meiggs and Harrington to break into online accounts at Google, Yahoo, and Facebook, among others. That’s because phone numbers often serve as a crucial communication channel for password reset links