The young man found himself spending the next nine years of his life working as a "ghost person", doing hard labour on various fishing boats in Indonesian waters without a valid seaman book or legal protection.
Now Komsan, at the age of 23, is finally home with his family in Kanchanaburi province, and he speaks emotionally about the ordeal he endured on foreign seas and the human trafficking that prevailed in the fishing industry.
"My friend told me I could make more money if I worked on a fishing vessel, so I joined the fishing crews at Mae Klong in Samut Songkhram province and went fishing in Indonesian waters," he recalled.
He said he willingly joined the fishing crew, but there were many victims of human trafficking who were there against their will.
"I received Bt10,000 (S$39.90) from the boss before I started working and received the rest of my wage when the boat returned to shore. However, some workers received nothing because they were lured into the work by an agent who would collect all their money plus up to Bt20,000 in commission fees. Hence the agent would get around Bt20,000 to Bt30,000 per head," he said.
Many deceived workers were treated worse than others; some bosses took these workers' salaries as compensation for the commission fees they had to pay agents, he said.
"In other cases, agents would bring newcomers to a karaoke restaurant to eat and drink and do whatever they liked. At the end of the night, they would receive an overly expensive bill. They would then have to work on the fishing vessels to pay their debt," he said.
Because of the shortage of fishermen, the owners of fishing vessels had to rely on the agents to supply workers for them, he explained. The agents found workers among rural people looking for jobs in Bangkok, and the targeted venues were places like railway stations and bus terminals. They often made lofty promises of well-paid jobs.
Komsan described himself as a "ghost person" in Indonesia because, on his first journey to that country, he was so drunk that he could not get back to the boat on time and he found himself stranded there.
"There are two kinds of ghost people, the workers who accidentally miss the return journey like me and the escaped workers who can't stand the brutality of the fishing vessel's captain or the hardship on board," he said.
"From what I have been through, working on fishing boats is hard work. The working hours vary, as it depends on each day's workload, but the crews usually have to work from 5 in the morning to 10 at night," Komsan recalled.
"If you are inexperienced or working slowly, you may be scolded or beaten by your captain or your co-workers," he added.
As an illegal immigrant in Indonesia, Komsan had to work for other boats by using a fake seaman's book to earn a living.
He also could not return to Thailand, as there would be problem with the captain.
"Most of the owners of the vessels have an Indonesian branch office. When I worked for their company, the office would issue a fake seaman's book for me so I could work for them without being caught by Indonesian border police," he said.
Komsan was recently rescued by a joint operation led by Thailand's Social Development and Human Security Ministry and returned to Thailand. "Now I just want to work in my home town and be near my family," he said.
About 4,000 fishery workers from Thailand, Laos, Cambodia and Myanmar are currently stranded in Indonesia, according to the Labour Rights Promotion Network Foundation.