After tying the knot earlier this year, Somjit and her husband visited the Wang Muang district office in Saraburi to register their marriage only to be told she was already married to a man she had never met.

Ms Somjit, 38, whose surname was not given, was shocked to learn of the prior marriage. She denied having known, let alone met, the Indian man who was supposed to be her husband.

This led the former cleaning lady for a private company to suspect that copies of her two most important documents -- her domicile registration and citizen ID card -- may have ended up in the wrong hands.

She remembers her supervisor at the cleaning department had collected copies of the two documents from her and now believes they were used to fake the marriage with the Indian man.

Ms Somjit filed a complaint with the authorities who revoked the bogus marriage.

Ms Somjit's case highlights a fraudulent practice in which foreigners, mostly from India, seek to obtain a marriage licence so they can stay in the country to run businesses which are not always legal, according to Natthaporn Sitthichai, a detective with the Public Sector Anti-Corruption Commission (PACC).

Some bribe district officials, who steal the identities of women in the citizenship database, to produce the marriage licences for them.

Ms Natthaporn said she found a number of women agreed to sign the marriage licences because they and the men were friends. Other women were hired or borrowed money from the men and agreed to the marriage to pay their debt.

On May 23, eight Indian nationals were detained for suspected involvement in a scam using the names of Thai women on forged marriage licences to stay in the country longer.

Deputy tourist police chief Surachate Hakparn said the arrests came after police took up complaints lodged by the women, including Ms Somjit, in Saraburi's Wang Muang district who found their names on marriage certificates despite never having been married.

According to the deputy commissioner, "the names of as many as 300 women in the district might have been used in the bogus marriage scam."

Pol Maj Gen Surachate said, so far, officials have helped 13 Thai women remove their names from the marriage registry.

Arthit Boonyasopat, director-general of the Department of Provincial Administration, said the department had sacked two Wang Muang assistant district chiefs and an administrative official in 2015 after they were found to have colluded in the scam.

The officials were accused of taking the names of 2,000 women to produce fake marriage licences in exchange for 2,000 baht a name. The case has been sent to the National Anti-Corruption Commission for a criminal investigation.