Prachuap Khiri Khan - Three members of a group calling itself Jit Arsa (volunteer spirit) are walking from Chumphon to the Foreign Ministry in Bangkok, calling on the government to reassert Thai sovereignty over a border village claimed by Myanmar.
The activists, who originally hail from the village in Ranong province, are Pitthaya Boonthawee, Somporn Kladsaeng and Prathuang Klomsook.
They left the Prince of Chumphon shrine in Chumphon for the 500km trek to Bangkok on Tuesday evening.
The activists are expected to arrive at the ministry in the next two weeks. Yesterday they crossed into Prachuap Khiri Khan province.
They want the government to claim back Ban Inthanin Kwang, which they say is located in Moo 9 of tambon Jor Por Ror in Ranong's Kra Buri district.
The village became the focus of a diplomatic incident in 2012 following a border dispute which saw Myanmar soldiers enter the village and arrest 92 Thai people living there.
The villagers were jailed for 77 days before being released.
However, Thais had lived in the village for decades, according to Mr Pitthaya.
The Myanmar army claimed the village was in Myanmar, he added.
Shortly after the incident the group demanded the Foreign Ministry help resolve the problem but nothing has happened since, Mr Pitthaya said.
"We will again submit a petition to the ministry. We want to make it clear that our village is located in Thai territory, not in Myanmar as claimed by their military,'' he said.
"We lived there for a long time. But Myanmar only recently claimed the village as part of its territory. How come?" he said.
Mr Pitthaya said there are only three marchers heading to Bangkok because the group did not want to flout the ban on political gatherings of more than five people.
He said the ministry needs to sit down with Myanmar officials and come up with some form of border demarcation in the area where the village is located.
No discussions on land demarcation have ever taken place, he said.
The ministry needs to take this case seriously or Thailand could lose a chunk of its territory, he warned.
Mr Pitthaya insisted there is strong evidence that dates back to the reign of King Rama IV that proves that more than 200,000 rai of land, which includes the present location of the village, belonged to Thailand.
It is wrong for Myanmar to say the land is theirs, he said.
About 1,000 Thais from 300 families settled in the area to establish the Ban Inthanin Kwang community and set up rubber plantations.
Thai officials had warned them several times not to remain there because of uncertainty as to which country had sovereignty.
Each time they refused to leave insisting the village was in Thailand before Myanmar troops raided the settlement on July 4, 2012.