Tigers are one of the world's most endangered species, with only 3,200 believed to remain in the wild.
About 200 of them are in western Thailand, but until recently it was thought that there were no tigers on the eastern side of the country.
Twelve tigers have been spotted in recent weeks in the east.
But tiger carcasses can sell on the black market for tens of thousands of dollars.
While the government is trying to track down tiger hunters, hope is waning as their population declines.
Al Jazeera's Aela Callan reports from eastern Thailand.