The families of three soldiers killed in Afghanistan were “intimidated” by a senior army officer on the final day of a coronial inquest, it’s been claimed.

The families of three Australian soldiers killed in Afghanistan were “intimidated” at an inquest by a senior army officer concerned about the release of classified information, a court has been told.

An emotion-filled final day of the coronial inquest into the deaths of Lance Corporal Stjepan Milosevic, Sapper James Martin and Private Robert Poate was interrupted on Friday by claims a brigadier took the soldiers’ next of kin aside and threatened to involve the attorney-general if sensitive defence information was released.

Cpl Milosevic, Sapper Martin and Pte Poate were gunned down by a rogue Afghan National Army soldier while on a mentoring mission at an Oruzgan province patrol base in August 2012.

The inquest has been held at the request of their families, who say the defence investigation was not independent or transparent.

The lawyer for Pte Poate’s family, Peter Bodor QC, told the inquest that during lunch on Friday the brigadier had addressed the soldiers’ next of kin “in an intimidating fashion”.

Mr Bodor said Brigadier Mark Holmes told the families an issue raised by Mr Bodor in open court should be redacted from an earlier written submission to the coroner and implied the case could be referred to the attorney-general.

Mr Bodor said the family members had felt “intimidated and powerless”.

“It’s a matter of the gravest of concern, the gravest impropriety,” he told the court.

Counsel for the Commonwealth James Renwick SC said Mr Bodor’s allegations were unfounded.

Deputy Queensland coroner John Lock agreed the incident was inappropriate in the final week of an inquest and said the material in question appeared to him to be “relatively innocuous”.

Over nine days the inquest has raised questions about how prepared the army was for a so-called green on blue attack, whether systemic failures in the defence force contributed to the soldiers’ deaths and how independent the army’s internal investigation was.

The final witness was the commander of the men’s Townsville-based regiment, who delivered a moving tribute to the fallen men which brought their grieving loved ones to tears.

Turning to the family members, Brigadier Roger Noble repeated in a breaking voice a prayer that had been read at a ramp ceremony held for the soldiers.

“It was a terrible day for the force, not just Australia,” he said

Outside court Pte Poate’s father Hugh said the inquest had been an ordeal but necessary because he felt the army’s internal report had been “superficial”.

“It’s been terrible to have to relive it and to have to go through it,” he told reporters.

“It (the inquest) is not something we wanted, from day one. But we felt we had to do it.”

The deputy coroner is not expected to release his findings until next year.