Crypto losses turn deadly as man accused of poisoning business partner with pesticide-laced coffee

A crypto investment dispute in Seoul has escalated into a criminal trial after prosecutors accused a 39-year-old man of attempting to kill his business partner by serving him coffee allegedly mixed with pesticide.

Authorities say the case stems from unresolved financial losses tied to a jointly operated Bitcoin investment venture. The Seoul Eastern District Prosecutors’ Office announced on Feb. 23 that it had arrested the suspect, identified only as A, on charges of attempted murder and violation of the Pesticide Control Act. The charges were filed on Jan. 9. A remains in custody pending trial, which is scheduled for 10:20 a.m. next month at the Seoul Eastern District Court.

Alleged Poisoning at Seoul café

According to prosecutors, the alleged attack took place around 9 p.m. on Nov. 23 last year at a café near Seokchon Lake in Songpa-gu, Seoul. During a meeting between the two men, A is accused of secretly adding methomyl, described by authorities as a colorless and odorless toxic insecticide, into the coffee ordered by his business partner, identified as B.

After consuming the drink, B reportedly lost consciousness and collapsed. He was transported to a hospital, where he regained consciousness three days later following medical treatment.

Investigators allege that A had purchased the pesticide online from China in October for 290,000 Korean won, approximately one month before the incident. Prosecutors contend that the purchase was made in preparation for the crime.

Investment partnership and financial dispute

The two men had been running an investment business together since 2022. Prosecutors claimed they pooled money through Bitcoin investment programs to profit. However, their business relationship soured after A allegedly failed to recover 1.17 billion Korean won, including company funds he had invested separately.

However, authorities have not shared more information about the structure of the investment programs, but they have pinpointed the unresolved losses as the root of the conflict between the partners. Prosecutors claim there was mounting financial tension leading up to the alleged poisoning attempt.

The case has attracted attention in South Korea alongside overall scrutiny of digital asset-related incidents involving both private and public institutions.

Broader crypto asset oversight developments

The supposed poisoning comes as South Korean authorities continue to address separate incidents that have to do with the handling of seized virtual assets. The Supreme Prosecutors’ Office recently sent new guidelines to prosecutors’ offices nationwide following a high-profile security breach involving confiscated cryptocurrency.

Last year, the Gwangju District Prosecutors’ Office lost 320 Bitcoins, worth about 30 billion Korean won at the then-market prices, after investigators accessed a phishing website while examining seized digital assets. During the incident, officials accidentally entered sensitive wallet information, including recovery information, which enabled the theft.

광주지검 검찰의 비트코인 320개 압수물 피싱 사건에 대한 후속 보도가 나왔는데요, 더 충격적인 내막이 있었습니다.

이번에 검찰이 비트코인 320개 잃어버리 전에, 경찰 수사과정에서 이미 비트코인 1400여 개가 사라졌다는 얘기가 있었다고 하는 겁니다. 이 말이 맞다면, 총 1720개가 사라졌다는…

— Cyp3er (@cyp3er) January 24, 2026

The 320.8 BTC stolen, worth about $21.4 million, were later returned by the unidentified hacker, according to local media reports. Authorities said they had blocked transactions involving the hacker’s wallet on centralized exchanges, hindering the hacker’s ability to liquidate the funds.

In response, the Supreme Prosecutors’ Office launched a plan to manage virtual asset holdings that required verification via designated official websites, such as blockchain.com for Bitcoin and Etherscan for Ethereum.

Meanwhile, further investigations are underway following reports by the Seoul Gangnam Police Station, which stated that 22 BTC stored in a cold wallet have been unaccounted for since 2021. The Gyeonggi Bukbu Provincial Police Agency said it has started an internal probe into the circumstances surrounding that loss.