South Korean police are seeking an arrest warrant for YouTuber Kim Se-ui, saying he faked evidence that defamed actor Kim Soo-hyun and helped spread false claims that the star had dated actress Kim Sae-ron while she was still a minor.

Investigators say Kim Se-ui manipulated screenshots of text messages and shared an audio file made with AI, then used them to fuel a story that shook South Korea and upended Kim Soo-hyun’s career. Police say he knowingly spread the claims for financial gain.

The case turns on material that first spread last year, shortly after Kim Sae-ron killed herself at 24. Months after her death, Kim Se-ui posted a voice recording in which the actress could be heard saying she had been dating Kim Soo-hyun since middle school, along with screenshots he said were text messages between them. Kim Soo-hyun has consistently denied the allegations. His agency initially denied that the two had ever dated, then later said he had been in a relationship with Kim Sae-ron for one year, but only when she was an adult.

Police now say the recording was generated by AI and that the screenshots were altered from messages sent from Kim Sae-ron’s phone to make it appear she had been texting Kim Soo-hyun. Kim Se-ui, who has nearly a million followers, posted a video calling the authorities’ allegations a “subterfuge meant to disrupt his investigation.”

The dispute reached far beyond one actor and one YouTuber. Kim Soo-hyun was once a household name in South Korea, where celebrities are held to high standards and subjected to relentless scrutiny. Kim Sae-ron had been seen as one of the country’s most promising young actresses before her death, and the allegations gained traction after her family publicly backed Kim Se-ui.

The next step is in the hands of prosecutors and the court that will decide whether the warrant is issued, while Kim Soo-hyun remains under psychiatric treatment and the criminal case over the fake evidence moves into its sharpest phase.