Southern Cross Austereo staff have reportedly been moved to safehouses and management have hired bodyguards as police investigate death threats against the company's employees.
About a dozen staff have been moved to hotels and up to 10 executives have been assigned bodyguards, costing the embattled radio company an estimated $75,000 a week, News Ltd reports.
A threat against Michael Christian, one of the DJ's whose prank call has been linked to the suicide of a British nurse, was received by mail on Thursday.
In the letter, which came from South Australia, it was made clear there were "bullets out there with your (Christian's) name on it''.
Further unreportable threats involving a shotgun were also made.
Police have spoken with Austereo staff about security and other matters and are also monitoring social media for other threats.
Security specialists could be guarding staff for months, News Ltd reports, as investigations in the UK could anger more people and cause more threats to be made.
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