A US soldier accused of killing 16 Afghan civilians in two rampages from his army post last year has reached a plea deal with prosecutors to avoid the death penalty, his lawyers have said.

Robert Bales is scheduled to enter guilty pleas to charges of premeditated murder on June 5 at a military base in the US, said his lawyer John Henry Browne on Wednesday. 

Bales was accused of shooting to death villagers, mostly women and children, in attacks on their family compounds in Kandahar province in March 2012.

"The judge will be asking questions of Sgt. Bales about what he did, what he remembers and his state of mind,'' Browne said.

A trial for Bales' sentencing is set for September, but the judge and the base's commanding general must approve a plea deal.

Emma Scanlan, another lawyer for the veteran of four combat tours in Iraq and Afghanistan, said that after his plea, a military jury would decide whether a life-term in prison for his crimes would include the possibility of parole.

An army spokesman, Major Gary Dangerfield, confirmed that a plea hearing was scheduled, but said he could not immediately provide other details.

'Crazed' and 'broken'

Bales slipped away from his remote southern Afghanistan outpost early on March 11, 2012, and attacked mud-walled compounds in two sleeping villages nearby. Most of the victims were women and children, and some of the bodies were piled and burned.

The angry protests which followed the attack prompted the US to temporarily halt combat operations in Afghanistan, and took US investigators three weeks to reach the crime scene.

A plea deal could inflame tensions in Afghanistan. In interviews with AP news agency in Kandahar in April, relatives of the victims became outraged at the notion Bales might escape the death penalty and even pledged revenge.

Browne previously had indicated Bales remembered little from the night of the massacre. But as further details and records emerged, Bales began to remember what he did, the lawyer said.

Browne added that Bales was contrite about the killings, and described him as “crazed and broken” on the night of the attack.

The defence team, including military lawyers assigned to Bales, eventually determined after having Bales examined by psychiatrists that he would not be able to prove any claim of insanity or diminished capacity at the time of the attack, Browne said.

At the time of the attack, Bales had been drinking contraband alcohol, snorting Valium and taking steroids before the attack.

Source: Agencies