THE Western world is on extremely high alert as ISIS identifies the Paris attacks as the "first of the storm".
The series of coordinated terror attacks killed at least 129 people in Paris on Friday night (French time) and is anticipated to set off a wave of similar, large scale attacks.
News.com.au reports terror experts have warned planning will be underway for coordinated attacks in European capitals. Australia has also been warned of the possibility of such terror attacks.
International policy expert Peter Jennings told Sky News Australia should be "very cautious" about the potential for copycat attacks "in the next week or so".
He said they could be carried out by individuals "who now think this is the moment to do something".
It could involve "one person working with one or two others, inspired by the Paris experience but not directed as closely by ISIS as the Paris action obviously was".
Terror expert Greg Barton from Deakin University in Victoria told news.com.au that at one level, all western countries and tourist hotspots are targets.
Barton says while Australia has an advantage by being isolated, in some ways the threat level was similar to what had been felt in Paris.
"In Australia we've got the same levels of radicalisation as France," he said.
"We have only have a tenth of the number in terms of Muslim population but the percentage of those being radicalised is similar to France."
Australian Prime Minister Malcolm Turnbull has expressed his confidence in the country's security as his government responds to the Paris attacks with reassurance.
New Zealand Prime Minister John Key has said the country's security threat remains as low, but was constantly being looked at.
Where could be next?
In terms of where will be targeted next, Deakin University terror expert Greg Barton says Turkey is probably the most vulnerable.
Last month, twin bombs at a peace rally in the country's capital, Ankara, killed at least 95 people and injured nearly 200 others.
Barton says Turkey will be hit again.
"It's opened itself up, opened up its borders perhaps in a foolish way, to vast networks of IS supporters and they've now got vast support networks there as well."
He says Belgium is also particularly under threat.
According to one analysis, Belgium has exported more jihadists to Syria and Iraq per capita than any other Western European nation.
CNN reports an estimated 440 Belgians had taken up arms for Sunni extremist groups in the Middle East, according to the International Center for the Study of Radicalization and Political Violence.
Two of the terrorists killed in the Paris attacks were Frenchmen who had lived in Brussels, Belgium's capital. Two cars linked to the attacks were rented in Belgium, and seven additional people have been arrested there.
Police have launched a manhunt in Belgium for another man suspected to have taken part in the Paris attacks with two of his brothers.
Barton told news.com.au Belgium's situation is "precarious" and they have an "even higher level of terror threat as France".
He said an attack on Paris was "almost inevitable", but what will be looked at now is whether there was a failure by authorities charged with preventing it.
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