Over 100 Thai women have reported to officials in Nong Bua Lamphu's Nong Sang district - the centre of the fake marriage-registration scam.
They include women who were really married and those whose identity was stolen, a district official, who asked not to be named, said.
The office's disciplinary probe committee was gathering information, while the Office of Public Sector Anti-Corruption Commission was also probing, the official said.
A former registrar allegedly sold some 600 women's names to foreign men, who used the names for fake marriage registration for immigration purposes from 2011 to 2013.
The registrar reportedly changed his name and is now an ordained monk somewhere in Khon Kaen, the official said.