Soldiers seized 1.2 million meth pills from suspected smugglers following a nighttime clash along the northern border of Thailand.

The Pha Muang Task Force intercepted around 10 backpack-carrying travelers while patrolling Chiang Rai province neighbouring Myanmar, at around 7:30 pm on April 2.

Officers from the specialised military united had halted the suspects at a checkpoint for an inspection, but were reportedly met with a barrage of gunfire from the armed group.

A fierce gunfight erupted with both sides exchanging fire for 10 minutes. No soldiers were injured in the skirmish but the alleged smugglers managed to flee across the border to Myanmar around two kilometres (one mile) away.

Thai troops waited until dawn to sweep the area with reinforcements. They discovered six bags left behind containing 1.2 methamphetamine pills.

The illegal goods were stamped with the number '999' - a trademark associated with Burmese drug lords.

Colonel Kidakorn Chantra, commander of the Pha Muang Task Force, said the drug interception was carried out following a tip-off that a large drug shipment was scheduled to arrive through the border at Chiang Rai.

He said: 'After completing the examination of the evidence, the Chao Tak Army Task Force, in coordination with the Pha Muang Force, has handed over all seized methamphetamine pills to investigators at Mae Fah Luang Police Station for further legal action. Our forces will continue to intensify border patrols to prevent drugs from entering the country.'

The Golden Triangle, where most of Southeast Asia's meth supply comes from, is found where the borders of Thailand, Laos, and Myanmar meet. But it has long been a feral nest of criminal activity, including opium production, meth labs and call centre scam bases.

At the heart of the Golden Triangle lies the Golden Triangle Special Economic Zone (GTSEZ), run by notorious Chinese business tycoon and suspected crime boss Zhao Wei in the Chinese vassal state Laos. Communist chiefs are said to turn a Nelsonian eye to his wrongdoing.

In 2007, Zhao brokered a deal with the Laos government and obtained a 99-year lease to build the zone on a 39-square mile patch of impoverished Bokeo province.

The Chinese businessman claims to be a benefactor as he touts the GTSEZ as a tourist and economic hub designed to bring more income and investments into the country. However, both local and international law enforcement agencies believe it is a front for organised crime, including human trafficking, drug trafficking, and call-centre scams.

International authorities have struggled to take down the gambling empire as the Laos government itself is said to be protecting the GTSEZ, in which it has a 20 per cent stake.