The emergence of the fake 100 baht bills follows reports and warnings of forged 500 and 1,000 baht notes found earlier there and in other provinces.
Pol Maj Gen Jeerawat Udomsud, chief of police in Trang, said on Thursday that since the discovery of 500 and 1,000 baht fake banknotes in Trang, forged bills of 100 baht denomination had started appearing there.
Two women grocery vendors who found them selves saddled with the fake 100 baht bills had already complained to local police in Muang Trang district - Patchanee Sukkhong, 37, and Sabai Satsen, 61.
The Trang police chief said the fake 100 baht billshad serial numbers beginning with 9A. The spread of fake notes in Trang was now a serious problem. Staff of the Bank of Thailand had been deployed in the province to monitor the situation and teach people how to detect the fake notes.