Troops, tourist police and officials from several agencies rounded up 126 Thais for allegedly taking advantage of foreign tourists around the Grand Palace, the tourist police chief said on Thursday.
The suspects were arrested in a joint operation on Wednesday, said Lt Gen Thirapol Kupatanon.
Those arrested included taxi drivers who refused to use their meters or who rejected passengers.
They also included street vendors who overcharged tourists, Thirapol added.
He said the officials also took record of 28 tuk-tuk and taxi drivers around Sanam Luang and Grand Palace to warn them not to take advantage of tourists.