An international hacking ring hacked into the computer system of a bank's London branch and obtained the account number of the ATM computer system's administrator, giving them access to the internal network and ability to remotely control ATMs. Hackers have also used malware installed on bank cards to empty cash from ATMs without a associated bank account by bypassing authentication. Another attack involved remotely installing malware called ATMitch on bank ATMs that allowed hackers to dispense cash at the touch of a button from a command center.