Thailand’s Prime Minister Anutin Charnvirakul has ordered an investigation into allegations of mass cheating in civil service exams to attain government jobs, after thousands of tests were allegedly tampered with to boost scores in exchange for fees of up to US$24,000 each time.

The scandal erupted after police and anti-corruption officials raided a company address in Nonthaburi outside Bangkok on Tuesday and found at least 10 officials on site tampering with computerised scores “to help applicants who had paid bribes” pass the exams.

Initial checks suggest bribes might have been paid for at least 3,000 tests from last year’s exams across the country.

The price for passing civil service exams through tampering ranged from 350,000 baht (US$10,500) to as much as 800,000 baht (US$24,000), officials said.

In a video of another bust in Petchabhun province linked to the initial raid shared by Thai police, a stunned civil servant in a khaki uniform explains how she became involved in the fraud.

“My friends,” says the woman, whose face is obscured in the video, admitting her job is to correct exam answers with a computer.

The municipality the woman represented – Wichian Buri, Petchabun province – took to social media to distance itself from the scandal, saying it “had no affiliation with, no prior knowledge of, and no participation whatsoever in the aforementioned fraudulent acts or corruption scheme”.