The Sydney Morning Herald and The Age have been told that the cameras that had been set up in the bathrooms were about the size of two 20-cent pieces, with the capacity to record for about two hours but not to transmit. The cameras used were not permanently installed, staff have been told, but it’s unclear for how long and with what frequency they were being placed near women’s toilets and showers.

Thamsongsana worked on the ground floor of the embassy and did not have access to the restricted area of the building, which is on another level. But Australian and Thai staff at the mission, where more than 250 people work, have been rocked by the security and privacy breach and the prospect that female employees were secretly recorded.

Staff were informed about the filming in bathrooms the morning following Thamsongsana’s arrest and counsellors and psychologists were brought in soon after.

Employees have also since been taken in groups into the bathrooms to show them where the cameras were suspected of being positioned.

Thamsongsana, who was held overnight in a remand centre in Bangkok last month, before being released on bail, has since emailed dozens of women at the embassy, imploring them not to proceed with their complaints against him and offering them compensation, the Herald and The Age has been told.

A spokesperson for Australia’s Department of Foreign Affairs and Trade said it could confirm that a former locally engaged staff member at the Australian embassy in Bangkok was arrested by Royal Thai Police on January 6.

“As this is an ongoing legal matter, the department is unable to comment further. The welfare and privacy of all staff remains a priority for the department and we continue to provide appropriate support,” the spokesperson said.

The police investigation over hidden cameras at the Australian embassy comes as a senior Thai naval officer has been accused of placing cameras in women’s bathrooms at his office.

A naval disciplinary committee has been set up after two cameras were last month found in the ceiling of a bathroom during electrical repairs.

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