The Lao workers were in Thailand to extend their passports when their van collided with a truck while running a red light, on Monday in Rayong Province.
Rayong Newspaper reports that three Lao women lost their lives, and eleven other Lao workers were hurt, alongside the Thai van driver.
Following the accident, emergency rescue services transported the injured and deceased workers to the nearby district hospital.
The investigation revealed that, prior to the collision, a truck stopped at the red signal at the crossing and the van crashed into the truck at a high speed.
One injured passenger said they had rented the van and were headed towards Chanthaburi province to extend their working visas. All the passengers were asleep when the accident happened.
The Thai police interrogated the driver of the truck and the van, as well as the passengers, after they recovered from their injuries.
According to witnesses, the van driver might have fallen asleep behind the wheels.
The police is investigating the incident further to find out the actual cause and release more information to the public.