Western Australia's premier has revealed threats were made against his wife and children in the latest security scare involving anti-vaccine mandate protesters.
Emergency services were called on Tuesday after a suspicious package was found at Mark McGowan's electorate office in Rockingham, south of Perth.
The package contained a substance which later proved to be non-harmful.
"A letter was sent addressed to my wife. It had white powder in it," the premier told reporters on Thursday.
"What they were intending was my wife would open it, and it contained a number of threats to harm her and my children and worse.
"Whoever did this is a coward of the highest order. And I just say to anyone out there who has any information about this, please provide that information to CrimeStoppers."
Mr McGowan confirmed the threats were related to his government's wide-reaching COVID-19 vaccine mandate policies.
The premier last year revealed he and his staff had received death threats over the introduction of vaccine mandates, prompting the temporary closure of his electorate office.
His personal security has since been increased.
Anti-vaxxers last month briefly blocked traffic on a Perth freeway, resulting in charges being laid against several people.
Some businesses have also had to deal with staff being threatened and abused while enforcing mandatory proof of vaccination and mask-wearing rules, in behaviour denounced by both sides of politics.
Police Commissioner Chris Dawson on Wednesday said several people were facing charges related to threatening shopkeepers.
"I am concerned about radicalised behaviours," he said.
"We have seen some very serious allegations - I know the premier's been threatened, I've been threatened, the chief health officer has been threatened - and some of these people are facing very serious charges. So we are taking this very seriously.
"Where people are threatening lives, committing criminal acts, we will make every effort to pursue and put the evidence before the courts."
