Jemaah Islamiyah (JI)

In essence, JI has a jihadist vision and wants to establish an Islamist state in the region, probably encompassing Brunei, Indonesia, Malaysia, Singapore, the southern Philippines and southern Thailand. Group factions differ over how to achieve this goal:

A minority group, led by Hambali, is interested in focusing on a broader anti-Western agenda similar to al Qaeda, and in effecting change in the near term….Opposing this faction is a majority group within JI, depicted as the "bureaucrats," that sees these tactics as undermining its preferred, longer term strategy of building up military capacity and using religious proselytization to create a mass base sufficient to support an Islamic revolution. (Source: CRS Report for Congress, Terrorism in Southeast Asia, updated February 7, 2005.)

• October 2002: A triple bombing in Bali killed over 200 people.
• August 2003: Bombing of the J.W. Marriott Hotel in Jakarta, Indonesia.
• September 2004: Australian embassy bombing in Jakarta that killed ten and wounded hundreds is thought to be a JI attack.

Read more: 2002 Bali Bombings the Deadliest Ever in Indonesia

The entire history of JI's leadership is not clear. It is assumed that an Indonesian operative, Riduan Isamuddin, who is known as Hambali, led or played a high level role in JI through 2002. Its current leader, Abu Bakar Ba'asyir, was convicted of involvement in the 2002 Bali bombings. He was released in 2006 and later exonerated for his actions.

JI's membership is estimated at between 500 and several thousand members, according to Southeast Asia security issues specialist, Zachary Abuza.

Jemaah Islamiyah is purported to have links with the Al Qaeda core group led by Osama bin Laden. Most media reports about JI describe it as "Al Qaeda linked," and Al Qaeda has laid claim to Indonesia as ripe for Islamist transformation. The depth of those links is obscure.

Read more about Al Qaida: Al Qaeda Global Jihadist Network | Al Qaeda Core Organization

A few JI members have acknowledged they had connections with the 9/11 attackers, two of who met with JI members in Malaysia in 2000. There is evidence they have provided safe haven for some AQ operatives, and helped finance global activities. Hambali, the alleged operations chief of JI (currently in US custody) denied any association with Al Qaeda, when questioned at Guantanamo Bay in April 2007.

The tsunami of December 2004 was one of the worst natural catastrophes in recent history. As such it provided an opportunity for Islamist extremists to recruit and expand their influence by aiding people in a vulnerable position. US humanitarian aid, provided through the Marines, was aimed in part at reducing the influence of JI and other such groups.