The vehicle procession was led by P-move and Save Bang Kloy – a group named after the Kaeng Krachan village in Phetchaburi where the evicted Karenni live.
Protesters demanded that the Natural Resources and Environment Ministry provide adequate farming land for the relocated villagers.
Protest leaders said the Karenni people had lived in the Kaeng Krachan forest long before they were designated as a national park in 1981. The Thai government sought Unesco heritage status for the park in 2010, relocating 57 Karenni families out of the forest with a promise to provide each with seven rai of fertile farmland.
But the families subsequently complained that the granted land was infertile and would not support crops.
Several families moved back to live in the forest early last year, prompting legal action to evict them.
The group called for the Natural Resources and Environment Ministry to halt legal action against 30 Bang Kloy villagers and 10 Save Bang Kloy activists.
They also called on the ministry to launch a new fact-finding committee to investigate land disputes of the Bang Kloy villagers, and amend the National Park Act, which they said violates the rights of forest-dwellers.
They demanded, too, that the government pass a “people’s bill” to protect the rights and livelihoods of ethnic minority groups.
At 1.30pm the procession headed to the Finance Ministry before arriving at the Natural Resources and Environment Ministry.