POLICE have confirmed that a suspicious white substance discovered at RAAF Base Amberley was washing powder.
Firefighters, police and ambulance crews were called to the base's mail room about 12.50pm after workers detected the substance while sorting through mail.
Four workers had to be decontaminated as part of the base's standard emergency procedure, with firefighters entering the building wearing special anthrax powder protection suits to investigate the substance.
The workers were hosed down for about 15 minutes each due to initial fears the washing powder could have been something sinister.
It took about two hours for a QFRS scientific team to confirm it as normal household washing powder - sent in the mail to an RAAF officer on the base from a family member.
Queensland Police Inspector Dave Preston said although authorities suspected from an early stage that the package was not dangerous, the proper protocols had to be followed.
"With the base here being one of the largest in Australia - there are security concerns 24 hours a day, seven days a week," Insp Preston said.
"We will always take this type of situation very seriously."
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