At least one of the raids took place in the Sydney suburb of Surry Hills
Counter-terrorism police in Australia have stopped a suspected plot to bring down an aeroplane, Prime Minister Malcolm Turnbull has said.
He was speaking after four people were arrested in raids across Sydney.
Investigators said they had seized materials in the raids that could have been used to make an improvised explosive device.
Mr Turnbull said the raids had been a "major joint counter-terrorism operation".
He said extra security was in place at domestic and international airports.
The raids took place in the Sydney suburbs of Surry Hills, Lakemba, Wiley Park and Punchbowl, Australian broadcaster ABC reported.
Australia's national terror threat level remains at "probable".
More at BBC News
Honestly its a new world order as far as terrorism is concerned; any Tom, Dick, Harry or Sally with a head full of bad wires and under the wrong influence can discharge highly unpredictable, terrible carnage anywhere. There's no stopping this crazy emerging trend of lone wolves or independent radicalized clusters. The best governments can do is introduce preventive education and not be slow to act on any intel however trivial or false it may seem.
This is a manifestation of consequences for Aussies opening their legs so damn wide for anyone and everyone to enter over the years; now they are getting ass-fucked.
SG government better be taking notes from this episode and dial back on its foreign trash policies pronto, because the same damn thing can jolly well happen to us. Or maybe something is already brewing on home soil who knows, and we are all still fucking oblivious to it.
Then again I doubt those monkeys in white will take heed; they need new citizens too badly to continually secure PAP's survival and their obscene million dollar salaries.