A group of farmers from Thailand are facing charges in Burma for allegedly growing rubber there illegally, Burma’s state-run media report.
The 61 men and women were detained last week near the two countries’ border, says the New Light of Myanmar newspaper.
A large number of vehicles and a cache of weapons were found in their possession, it added.
Thai officials say the farmers believed they had permission to work there.
The Burmese army arrested the 52 men and nine women for “illegally operating” 1,500 acres (607 hectares) of rubber plantations, says the New Light of Myanmar.
“The Thai detainees have encroached upon Myanmar’s territory and worked rubber farming on a commercial scale and held arms and ammunitions for their security,” the newspaper said, adding that Thai officials had already been informed of the detentions.
Among the weapons reportedly seized were different types of guns, bullets and a grenade. There were also three bulldozers and more than 30 vehicles.
Thai authorities argue that this is just a case of misunderstanding, but the decision to still press charges reveals a certain frostiness in cross-border relations, according to the BBC’s Jonah Fisher.
Burmese President Thein Sein is scheduled to visit Thailand later this month.
If the farmers are still being held then, their fate is likely to form a major part of the talks, our correspondent adds.