Arrest warrants will be issued against four suspects of a transnational heroin trafficking gang after a thorough investigation in Chon Buri, according to the Office of the Narcotics Control Board (ONCB).
The probe led to the to the seizure of 314 kilogrammes of heroin en route to Australia.
ONCB secretary-general Wichai Chaimongkhon yesterday revealed the bust after a meeting last Friday with representatives of Vietnam, Laos and Australia during an investigation into the drug network.
The meeting shared evidence which will result in four arrest warrants being sought against two Thais and two foreign nationals, Mr Wichai said.
The investigation came after Seaport Interdiction Task Force (SITF) seized 314kg of heroin hidden in 135 paint buckets at Laem Chabang port in Chon Buri and caught a suspect, identified as Tukta Boonbanlu, on July 6.
Mr Wichai said customs officials at the port discovered something suspicious during an X-ray scan.
The officials inspected the items which were categorised as "red-line goods".
After an examination, it appeared heroin was contained in 134 boxes, weighing 314.63kg, worth 943.89 million baht.
The act was in breach of the Customs Act and the Narcotics Act, senior police said.
An investigation indicated the heroin was trafficked from the border in the Northeast and was bound for Australia.
Based on a preliminary investigation, the shipment was linked to a previous trafficking attempt, in which the drugs were stuffed in motorcycle tyres bound for Taiwan and Australia.
The suspects were likely connected with a transnational network in Thailand, Vietnam, Laos and Australia, Wichai said.
In a separate development, the army's Pha Muang task force said it clashed with a drug trafficking gang at the border, leading to a seizure of 600,000 meth pills and 8kg of opium in Mae Ai district of Chiang Mai.
Pha Muang Force commander Maj Gen Narit Thawornwong said the forces were scouring the border near Ban Huai Poo village in tambon Tha Ton when they encountered 7-8 traffickers heading into the territory.
They asked for a search, the gang refused, and the two sides exchanged gun fire for about five minutes.
The group later fled the area, leaving the drugs which were hidden in six bags.
The items were taken to the Mae Ai police, Maj Gen Narit said.
Maj Gen Narit said narcotics gangs were still able to distribute to drug users, and producers across the border were still able to trade in drugs despite the Covid-19 situation and unrest in Myanmar.
Forces have been beefed up along the borders in Chiang Mai and Chiang Rai as drug traffickers attempted to break through the North due to movement restrictions and lockdown measures in Laos, he added.