An urgent safety warning has been issued for Queensland after a drug 10,000 times more potent than morphine was found in Brisbane.
Carfentanyl, a powerful anaesthetic used to sedate elephants, was intercepted at a Brisbane mail centre by Australian Border Force officials.
The discovery prompted an urgent warning from Police Minister Mark Ryan.
"I am advised that Carfentanyl is a highly toxic and potent synthetic based drug, with a 0.002mg dose enough to kill a person," Minister Ryan said.
"The fact that this illegal drug has been located in Queensland is very concerning and together with the police, we are urging people to not take any risks at all with this illicit drug."
According to Time Magazine, just a few granules the size of table salt can be lethal for humans.
It has already had an impact in the United States, where about 300 people overdosed in a month last year.
However, police said it is relatively new in Australia with one confirmed detection in Sydney by the ABF in December 2016 and now this most recent detection in Queensland.
"We are very concerned to see this drug in Queensland," Detective Superintendent Jon Wacker of the QPS Drug and Serious Crime Group said.
"Because of its capacity to cause death, it is important we get the message out as soon as possible to the community.
"Make no mistake, these are not party drugs. These are dangerous drugs and it's not a matter of if it will kill you - this drug will kill you."
Information suggests anyone who comes into contact with the drug on their skin or eyes is also at great risk.