WA man sentenced over Bunbury siege

A man has been sentenced to more than four years in a psychiatric facility after he choked a hostage with a chain while armed with a spear gun during an overnight siege in the WA town of Bunbury.

David Charles Batty had been on the run from a mental health facility for about a year when he held laundromat owner Peter Anthony Williams captive in a park and threatened to detonate explosives - which he did not have - in July 2015.

At the time, he had been awaiting a sentence for taking his elderly father hostage, armed with a gas cylinder and a lighter, for four hours at Perth's Kings Park three years earlier.

He was ordered in March 2016 to spend one year in Graylands Hospital's Frankland Centre for the 2012 offences.

On Wednesday, he was sentenced to a further four years and nine months over the Bunbury siege.

Batty will be eligible for parole in November 2019 but has a profound mental illness, schizophrenia and a paranoid delusional disorder, so is expected to continue needing treatment.

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