Apple’s sudden removal of the Activation Lock status checker from its website could have been in response to its use in hacking locked iOS devices, MacRumors speculated in a new report. A video posted by REWA Technology illustrates a process for finding valid serial numbers using the Activation Lock status checker and using those numbers to unlock an iPhone or iPad. Apple hasn’t confirmed any reason for shutting down the website, but since September, some users trying to activate new or restored iPhone 6s, 6s Plus, 7 and 7 Plus models have reported finding their phones locked to another Apple ID, and only Apple has been able to fix the problem. The full video of the hacking method used can be seen below, but without the steady supply of valid serial numbers previously available from Apple’s website, the process is now useless.