Two packages containing white powder that washed up on southern Queensland beaches in recent days have prompted police and the State Emergency Service to search beaches along the Fraser Coast for similar packages.
Superintendent Craig Hawkins said police suspected the packages contained an "illegal or illicit substance".
"The early indications are that it's an illegal substance but until we have it formally analysed by our forensic analysists we won't know for sure," he said.
Police were alerted after a one-kilogram package was discovered at Elliott Heads last Friday, and another was found yesterday further north at Mon Repos.
"Obviously the nature of the way it was packaged and the way it's been presented certainly we strongly suspect it's an illegal substance," Superintendent Hawkins said.
He said police and Australian Border Force agents have been trying to determine where the packages came from.
"At this stage, we're investigating firstly what the nature of that product is and secondly where it might have come from," he said.
Superintendent Hawkins said authorities were especially concerned because of the high number of tourists and children in the areas where the packages were found.
"The concern, obviously, is that there may be more out there and the primary concern for us is the issue that might impose by somebody that finds it and handles it in a manner that causes themselves harm," he said.
"We are very concerned that it may lead to a tragic outcome.
"We have searches underway along that beachfront and additionally not only by land but a search is underway by water to try to find any others that might be there."
He warned anyone who found a suspicious package in the Fraser Coast region should leave it alone and call police immediately.
