A man has pleaded guilty over a "bizarre" knife attack in Queensland after stabbing a Gumtree seller and his elderly mother while buying a printer.
Adam Curtis Brown was initially charged with attempted murder after attacking a 50-year-old man and his 82-year-old mother in Hervey Bay in April 2018 while collecting the online purchase.
Brown told Brisbane Supreme Court in June 2019 that he was intoxicated by printer fumes at the time of the attack.
On Thursday he pleaded guilty in Brisbane Supreme Court to downgraded charges including malicious act with intent and assault occasioning bodily harm while armed.
"I have read a statement of facts. It does seem ... bizarre behaviour," Justice Paul Freeburn said on Thursday.
The matter has been adjourned until next week with defence barrister James Godbolt waiting on a psychiatrist's report.
"It's hard to avoid the inference ... that there is some mental health element to all of this," Justice Freeburn said.
Crown prosecutor Chris Cook did not oppose the adjournment.
"Objectively it is senseless violence on the face of the statement of facts - what was going on in Mr Brown's mind is another matter of course," he said.
Brown has been in custody since the attack - more than four years - and appeared via video link from Maryborough Correctional Centre.