An inquest into the deaths of three Australian soldiers in Afghanistan has heard that no precautions were taken to prevent insider attacks despite warnings

Armed Afghan National Army soldiers were allowed to mingle with Australian defence force personnel at a desert patrol base where three diggers were killed in an insider attack, an inquest has heard.

A coronial inquest into the August 2012 deaths of Lance Corporal Stjepan Milosevic, Sapper James Martin and Private Robert Poate has heard that on the night they were shot dead by a rogue Afghan soldier there was no additional security at the base, despite warnings of an increased threat of so-called green on blue attacks.

Appearing at the Brisbane inquest, Adam Burke, the former platoon sergeant at the patrol base in Oruzgan province, said he had been aware there was a heightened threat of such incidents due to the Ramadan festival.

However, Sergeant Burke, under questioning from counsel assisting the deputy state coroner Anthony Marinac, said he had not known of the recent issuing of a fatwa that promised ascension to heaven to those who killed western soldiers.

Sgt Burke said Afghan soldiers, some armed, were allowed to wander around the Australian camp at the patrol base, 20km north of Tarin Kowt.

“Personally I wasn’t completely comfortable with them being there, but if I’d just had have told them to leave it wouldn’t have been conducive to building rapport and mentoring,” he told the inquest.

Sgt Burke conceded there was only one roving Australian guard on watch that evening and more personnel would have been necessary to adequately guard against an insider threat.

Despite this, a defence inquiry into the deaths found there had been no systemic failures responsible for the fatalities and made no recommendations to prevent similar attacks.

The dead soldiers’ families, who requested the inquest, say the defence investigation was neither transparent nor independent, and they were left out of the process.

A military legal officer who helped manage the defence inquiry testified that the type of inquiry held was relatively cheap and less intensive but denied cost was a major factor.

Colonel James Waddell said a more expensive and wide-ranging defence commission of inquiry had been considered unnecessary because it wouldn’t have shed more light on what happened.

“However tragic, the deaths of servicemen in Afghanistan was an expected outcome of deploying to a war zone,” Colonel Waddell told the inquest.

“We’re not dealing with incidents that can be equated, for example, to accidental deaths in training in a peacetime environment.”

Lance Corporal Milosevic’s widow, Private Poate’s parents and Sapper Martin’s mother attended the first day of the hearing, which is scheduled to run for about one week and hear from 10 more witnesses.

The Afghan National Army sergeant responsible for the attack, named Hekmatullah, has been sentenced to death.