Estimates suggest that at least 150,000 migrants from Cambodia were working in Thailand before the exodus in June, 2014.
Fearing a crackdown on illegal immigration from the Thai military, over 120,000 Cambodian migrants crossed the border and returned to Cambodia in one week.
Thai Immigration Police met migrants at the railway station in the border town of Aranyaprathet, recorded their identities and accompanied them to the border crossing.