A key member of the infamous Ryuk ransomware gang has been extradited to the US after his arrest in Kyiv, Ukraine.

The 33-year-old man was detained in April 2025 at the request of the FBI and arrived in the US on 18 June to face multiple charges.

The suspect played a critical role within Ryuk by gaining initial access to corporate networks, which he then passed on to accomplices who stole data and launched ransomware attacks.

Ukrainian authorities identified him during a larger investigation into ransomware groups like LockerGoga, Dharma, Hive, and MegaCortex that targeted companies across Europe and North America.

According to Ukraine's National Police, forensic analysis revealed the man's responsibility for locating security flaws in enterprise networks.

Information gathered by the hacker allowed others in the gang to infiltrate systems, steal data, and deploy ransomware payloads that disrupted various industries, including healthcare, during the COVID pandemic.

Ryuk operated from 2018 until mid-2020 before rebranding as the notorious Conti gang, which later fractured into several smaller but still active groups. Researchers estimate that Ryuk alone collected over$150 million in ransom payments before shutting down.