The US soldier who murdered 16 Afghan villagers last year has been sentenced to life in prison without the possibility of parole, BBC News said.

Staff Sgt Robert Bales, 40, opened fire on men, children and women during the attack in Kandahar on 11 March 2012.

The father of two pleaded guilty in June to avoid the death penalty.

He apologised during his sentencing hearing at a Washington state military base on Thursday, calling the attack an "act of cowardice".

Sgt Bales had been making a case for why he should one day be eligible for parole, which would have meant he could have been released in 20 years.