The defence department says a member of the Australian Defence Force is a “person of interest” in investigations after a video recording device was found in a bathroom on HMAS Leeuwin, in what the chief of navy called a “despicable betrayal of trust”.

A day after senator Jacqui Lambie told the Senate that a hidden camera had been found in a female shower facility onboard the naval ship, docked in Cairns, navy chief Matt Buckley confirmed a “video recording device” had been located in one of the ship’s bathrooms.

In a statement, Vice Adm Buckley called the incident an “act of sexual violence” and “the most despicable betrayal of trust”, and said the navy was conducting a review of all bathrooms across the service.

Defence confirmed on Wednesday that a “video recording device” was found in the cabin of the vessel, which it had referred to the Joint Military Police Unit. It came hours after Lambie – an ADF veteran and advocate for defence personnel – told the Senate she’d been contacted by a former member of the navy with allegations about a camera being found aboard HMAS Leeuwin.

Defence did not initially confirm where the device had been found, or any details about its investigation.

On Thursday, the department gave a further update.

“An Australian Defence Force member has been identified as a person of interest in the investigation into a video recording device being located on Royal Australian Navy ship HMAS Leeuwin,” the department said.

“This person is now assisting the Joint Military Police Unit with its enquiries. Navy’s focus and priority is providing support to those who are impacted by this incident.”

In a written statement, Buckley informed navy members of the update.

“I consider this a most serious matter, and accordingly, the Ship’s program has been altered to enable a rapid and rigorous investigation by the Joint Military Policing Unit,” he wrote.

“My highest priority, as always, is the wellbeing of our people.”

Buckley said the navy was conducting a “100% audit of all of our bathrooms across the Fleet”.

“This act is the most despicable betrayal of trust and is fundamentally misaligned with our values,” he said.

“You have my assurance and commitment that we will tackle this act of sexual violence with all of our energy. Any perpetrator will be held to account. Further, you should all know that eradicating sexual violence in our workplace is fundamental to the fighting efficiency of our Navy. I invite all of you to make this your priority.”

The defence minister, Richard Marles, described the incident as “reprehensible, invasive and … the most despicable breach of trust”. He said he was receiving updates on the investigation as it continued.

“There is no place for this behaviour in the Australian Defence Force. Our priority remains supporting the individuals who have been impacted,” he said in a statement on social media on Thursday.

On Wednesday, Lambie asked whether images captured by the device had been published online.

“How many of our female sailors have unknowingly been recorded in their most private moments? How much footage has been distributed online so far, retained or uploaded without knowledge or consent? These are the questions today I ask navy,” she said.

Buckley said “all potentially impacted personnel are receiving our strongest support”, adding that the warrant officer of the navy was in Cairns to support the ship’s company.