The University Hospital Centre in Zagreb, Croatia, was hit by a cyberattack on 27 June, claimed by the LockBit ransomware group. The attack crippled the hospital's networks, forcing emergency patients to be redirected to other facilities. Despite the disruption, hospital officials assured that patient safety was never compromised. Over 100 experts worked tirelessly to restore the IT systems, bringing the hospital back online within 24 hours.

LockBit, a Russian-affiliated ransomware group, posted on its dark leak site that it had stolen a large cache of sensitive data from the hospital in Croatia, including medical records and employee information. The hospital has not confirmed the specifics of the stolen data but has involved the authorities, and a criminal investigation is underway. LockBit, operating since 2019, has been linked to over 1,400 attacks globally and continues to evade law enforcement despite setbacks like the FBI and Interpol's Operation Cronos.

The attack on KBC Zagreb coincided with multiple cyberattacks on Croatian government agencies by another Russian-linked group, NoName057(16). Known for targeting the critical infrastructure of nations supporting Ukraine, NoName denied responsibility for the hospital attack, emphasising their principle of not targeting medical facilities. NoName has been responsible for numerous cyberattacks across Europe, affecting several countries' banking systems and critical infrastructure.