CHIANG RAI – Thailand’s Office of the Narcotics Control Board (ONCB) launched the second round of an operation called “Tumor Removal,” expanding an investigation tied to major crystal meth seizures near the Chiang Rai border.
The case now connects to a large cross-border drug network allegedly led by “Sia Jiw,” a former inmate accused of posing as a high-ranking military figure to avoid detection.
This latest action led to the arrest of two military officers. Officials identified one as a lieutenant colonel under the Office of the Permanent Secretary for Defense, accused in a money-laundering case. The second is a first lieutenant from a special forces unit, accused of transporting narcotics into Thailand as part of the same network.
Drugs Seized in Mae Fah Luang District
The investigation grew from an incident on December 26, 2024. Soldiers from a local task force under the Pha Muang Task Force intercepted a pickup truck in Mae Fah Luang District, Chiang Rai. Inside, officers found 44 sacks of crystal meth with a total weight of about 1,418 kilograms.
Investigators also recovered a mobile phone from the vehicle. After reviewing communications, including activity on the LINE app, they say the trail pointed to the alleged organizer, Chutithan (known as “Sia Jiw”). Authorities describe him as an ethnic minority member who had previously been arrested in a heroin case in 2006.
The network used fake military markings to move drugs
After serving time, authorities say Sia Jiw changed his name and surname and later returned to drug trafficking. Investigators allege the network moved drugs from the northern border to the south, then prepared shipments onward to third countries.
On March 8, 2025, officers tracked a 6-wheel truck that allegedly carried false license plates and was made to look like a military vehicle. A firefight reportedly occurred in Mae Salong Nok, Mae Fah Luang District. When officers searched the truck, they found more than 1,400 kilograms of crystal meth hidden in a fuel tank.
Authorities arrested seven suspects in that incident. Officials said three of them were former soldiers who had been discharged earlier due to narcotics cases. Investigators believe those ex-soldiers later worked as armed escorts and transporters for the network.
On February 12, 2026, ONCB officers, working with Provincial Police Region 5, carried out searches at eight locations across Chiang Mai, Chiang Rai, Nonthaburi, and Bangkok. Those raids led to the arrest of:
- Sia Jiw’s wife (identified as Sirinda)
- A man named Siwasan, accused of sourcing vehicles
- First Lieutenant Chokchai, a serving officer under a special forces command, was accused of working on the transport team
Authorities also announced the seizure and freezing of more than 47 assets. The list included real estate, bank deposits, vehicles, firearms, gold jewelry, and cash. The estimated total value exceeded 122 million baht.
Money trail allegedly linked to lieutenant colonel and family members
After the raids, investigators traced financial transactions tied to the network. They say the money trail led to a lieutenant colonel, his wife, and relatives on the wife’s side of the family. According to officials, evidence showed multiple transfers worth millions of baht coming from accounts linked to Sia Jiw’s network.
Investigators also claim the wife’s relatives acted as nominees, holding high-value assets on behalf of Sia Jiw and his wife.
Based on the evidence, the investigative team sought arrest warrants from the Chiang Rai Provincial Court for the lieutenant colonel and his wife on charges related to conspiracy to commit serious narcotics offenses.
Authorities said they moved in on February 25, 2026, and arrested Lieutenant Colonel Pan (identified as serving under the Office of the Permanent Secretary for Defense) along with his wife. The arrests took place near Soi Chaeng Watthana 25 in Bangkok.
Officials said Sia Jiw remains a fugitive. Still, ONCB leaders believe the arrests of two serving officers helped weaken the network’s logistics and financial support.
ONCB officials also referenced earlier intelligence. They said that in 2019, Taiwan’s coast guard notified Thai authorities about a case involving Thai and Taiwanese suspects accused of smuggling 29 kilograms of heroin into Taiwan. Officials claimed Sia Jiw was linked to that case.
