Experts say the main danger posed by the Indonesian terror group, which was responsible for the 2002 and 2005 Bali attacks and is affiliated with al-Qa'ida, is that it has mutated into a plethora of militant splinter groups, each of which is capable of causing mayhem.
Since the October 12, 2002, attack on Bali, which killed 202 people, including 88 Australians, more than 400 members of the terrorist organisation have been arrested across four countries.
A massive security crackdown by Indonesian and Australian police has led to the capture of 50 senior terror leaders and forced a significant change to the group's paramilitary operations.
But Jakarta-based JI expert Sidney Jones says the biggest threat to Western targets and civilians is no longer from an attack sanctioned by the JI leaders, but from the militant breakaway groups.
"The risk of an attack on civilians endorsed by the JI leadership is now very low," said Ms Jones, director of the Southeast Asian branch of the International Crisis Group.
"The biggest threat now is that the younger militants of JI couldbe used as a recruiting pool for splinter groups like that of(Bali bomber) Noordin Mohammed Top."
Ms Jones said the fugitive Top and his followers were still in favour of launching attacks on Westerners and their group was continuing to attract support.
Australian Federal Police Commissioner Mick Keelty said the Indonesian National Police had made significant inroads into the dismantling of JI's stronghold over the past five years.
The INP has enjoyed many successes breaking down the original hierarchical structure of JI, including the arrests this year of senior leaders Abu Dujanah and Zarkasih.
"In fact, the INP has been more successful in terms of arrests and dismantling of a terrorist group than probably any other law-enforcement agency in the world," Mr Keelty said.
"While these arrests have reduced the overall strength and reach of the group, the threat they pose remains tangible.
"The pressure which the INP has placed on the network has broken down the hierarchical structure of the organisation, and we have seen the formation of informal networks."
Along with the Bali attacks of 2002 and 2005, the group has been blamed for a string of bombings across Indonesia, including the attack on the Marriott Hotel in 2003 and the Australian embassy bombing in 2004.
But it has been significantly weakened in the past five years with the capture in 2003 of the al-Qai'da-linked Bali bomb mastermind Hambali, the killing of Bali bomb-maker Azahari bin Husin in November 2005 and the capture in June this year of its most recent military leader, Abu Dujana.
Since the devastating Bali attack in 2002 - the fifth anniversary of which is on Friday - Australian and Indonesian police have worked closely together to hunt down JI's militants.
Much of the success can be attributed to the police units that were set up in the wake of that attack, the intelligence-gathering taskforce and the crack Indonesian counter-terrorism squad known as Detachment 88.
But international terrorism experts agree that JI is regrouping and continuing to recruit new members, starting in schools around Indonesia.
Ms Jones says JI is regrouping, but not with plans for the same type of paramilitary operations it once planned. "What is different now is that they don't have the Malaysian and Singapore mantiki (military training divisions) or the leadership with the al-Qai'da connections," she said.
After the arrest of Hambali, it was through Abu Dujana, who is fluent in Arabic, that JI maintained its links to al-Qa'ida.
Ms Jones said the organisation still had strong bonds and that there was enough of a social network to survive 100 more arrests. And she warned that the return to Indonesia of fugitive JI members Dulmatin and Patek, who have been hiding out in The Philippines, could provide the focus for a new splinter group.
Patek, Dulmatin and Top are Australia's most wanted terrorists. The US Government has a $US10 million ($11.1 million) bounty on Dulmatin's head, surpassed only by the $US25 million offered for Osama bin Laden.
Top, who has been on the run for five years, is now considered less of a threat because he has lost most of his inner circle and is finding it difficult to operate.
But Ms Jones warns that he should not be discounted until he is behind bars.