Police have confirmed the white powder sent to Troy Buswell’s Busselton electorate office was flour.
The office was locked down yesterday after the discovery of a letter containing the suspicious powder.
Police spokesman Inspector Dominic Wood said it was likely the package was connected to suspicious letters sent to Premier Colin Barnett, Treasurer Mike Nahan, Parliament House, The West Australian and the Taxi Board last week.
The package arrived at Mr Buswell’s Prince Street office, where a member of his staff discovered it while sorting through the incoming mail.
The staffer immediately called Busselton Police, who evacuated the building as a precaution.
Letters found to contain flour and the written threat: “If the powder doesn’t get you, the bomb will”, sparked lockdowns and evacuations at Mr Barnett and Mr Nahan’s offices, the Riverton Shopping Centre, the domestic airport mail centre and State Parliament last week.
Insp Wood said it was not yet known whether the envelope sent to Mr Buswell contained a similar threat.
Security around senior ministers was tightened in the wake of the scare, with the police State Security Unit also examining mail screening procedures at MP’s electorate offices.
Police are yet to identify the specific threat or motive behind the campaign, but last week said it was unprecedented for this number of public figures to have been targeted in Western Australia.