They say Australia should expect a surge of religious extremism and even terrorism.
Federal and state police and other agencies stepped up cult monitoring last week after Israeli police arrested 14 members of a US-based doomsday cult in Jerusalem.
Acting Prime Minister Tim Fischer told The Sunday Mail yesterday: "It's getting crazier month by month in the lead-up to the new millennium."
But he was confident Australian authorities could "pick the loonies and deal with them".
AFP spokesman Terry Brown said federal police would act if national security was threatened, but their hands were tied until the cults broke the law.
Doom cults head here
Israeli authorities claim the Concerned Christians cult hoped to trigger the second coming of Jesus Christ and Armageddon by massacring people at holy sites across Israel.
However, Queensland cult specialist Jan Groenveld said the doomsday merchants were more likely to come to Australia. "If it's a biblical cult, they may go to Israel, but eastern, Nostradamus-based and UFO-based cults believe the southern hemisphere, in particular Australia, may suffer less or later damage as the end approaches."
Cult leaders had predicted humanity would be annihilated after nuclear warfare, natural disasters such as floods, asteroid and comet strikes, economic ruin, and civil chaos sparked by the Y2K computer bug. Mr Fischer said he personally had closely monitored the Concerned Christians' activities.
"It could become a worry (here). I have followed developments in Jerusalem and I hope violent cults overseas won't be mirrored in Australia." Mrs Groenveld's theory is backed by Garry Greenwood, once the second highest ranking official of the Mahikari movement in Australia. He is an expert on Mahikari and its deadly sister cult Aum Shinri Kyo, behind the 1995 Tokyo subway nerve gas attack that killed 12.
"Both sects believed an Armageddon war would soon annihilate Japan and much of the world, and that they needed to establish safe havens in the southern hemisphere, which is why they ventured to Australia," he said.
But low-key, home-grown doomsday cults in ordinary suburban houses were as much a concern, Mrs Groenveld said.
One called The Group, on Brisbane's southside, claimed to be "God's executioners", alert and ready to rid the scourge of humanity, "They have a stash of guns they continually move and the leader himself has a samurai sword." Mrs Groenveld said cults such as Twelve Tribes Mission, a US cult with Australian members in Picton NSW, who also believed themselves part of God's clean-up army at Armageddon, were feared to be potentially militant in Australia. 'There are people out there all over the place who would like to be another Jim Jones'