Jemaah Islamiah (Arabic: الجماعه الإسلاميه, al-Jamāʿh al-Islāmiyah, meaning “Islamic Congregation”], frequently abbreviated J.I., is a Southeast Asian militant Islamic organization dedicated to the establishment of a Daulah Islamiyah (Islamic State) in Southeast Asia incorporating Indonesia, Malaysia, the southern Philippines, Singapore and Brunei. JI was added to the United Nations 1267 Committee’s list of terrorist organizations linked to al-Qaeda or the Taliban on 25 October 2002 under UN Security Council Resolution 1267.
JI has its roots in Darul Islam (DI, meaning “House of Islam”), a radical movement in Indonesia in the 1940s. JI was formally founded on 1 January 1993 by JI leaders, Abu Bakar Bashir and Abdullah Sungkar while hiding in Malaysia from the persecution of the Suharto Government. After the fall of the Suharto regime in 1998, both men returned to Indonesia where JI gained a terrorist edge when one of its founders, the late Abdullah Sungkar, established contact with Osama Bin Laden’s al-Qaeda network. 
JI’s violent operations began during the communal conflicts in Maluku and Poso.. It shifted its attention to targeting US and Western interests in Indonesia and the wider Southeast Asian region since the start of the US-led war on terror. JI’s terror plans in Southeast Asia were exposed when its plot to set off several bombs in Singapore was foiled by the local authorities.Recruiting, training, indoctrination, financial and operational links between the JI and other militant groups, such as al-Qaeda, the Abu Sayyaf Group (ASG), the Moro Islamic Liberation Front (MILF), the Misuari Renegade/Breakaway Group (MRG/MBG) and the Philippine Rajah Sulaiman movement (RSM) have existed for many years, and continue to this day.
Jemaah Islamiah is known to have killed hundreds of civilians in the Bali car bombing on October 12, 2002. In the attack, suicide bombers killed 202 people and wounded many in two blasts. The first, smaller blast by a suicide bomber using a backpack, killed a small number of people in a nightclub and drove the survivors into the street, where the vast majority were killed by a massive fertilizer/fuel oil bomb concealed in a parked van. After this attack, the U.S. State Department designated Jemaah Islamiah as a Foreign Terrorist Organization. Jevolved in dozens of bombings in the southern Philippines, usually in league with the ASG.
However, maah Islamiah is also strongly suspected of carrying out the 2003 JW Marriott hotel bombing in Kuningan, Jakarta, the 2004 Australian embassy bombing in Jakarta, and the 2005 Bali terrorist bombing. The JI also has been directly and indirectly inmost of Jemaah Islamiah prominent figures such as Hambali, Abu Dujana, Azahari Husin, and Noordin Top have either been captured or killed, mostly by Indonesian anti-terrorist squad, Detachment 88. While several of its former leaders, including Malaysian jihadist and Afghanistan War veteran Nasir Abbas, have renounced violence and even assisted the Indonesian and Malaysian government in the war of terrorism. Nasir Abbas was former superior to Noordin Top.History
The JI was established as a loose confederation of several Islamic groups. Sometime around 1969, two men, Abu Bakar Bashir,and Abdullah Sungkar, began an operation to propagate the Darul Islam movement, a conservative strain of Islam. Darul Islam was almost eliminated in the 1950s after members belonging to that sect instigated a rebellion in an effort to create an Islamic state in parts of Indonesia.
Bashir and his friends created a pirated radio outfit to preach to the poor and oppressed in Indonesia. Bashir created a boarding school in Java. The school’s motto was, “Death in the way of Allah is our highest aspiration.”
Bashir and Sungkar were both imprisoned by the New Order administration of Indonesian president Suharto as part of a crackdown on radical groups such as Komando Jihad, that were perceived to undermine the government’s control over the Indonesian population. The two leaders spent several years in prison. After release, Bashir and his followers moved to Malaysia in 1982. They recruited people from Indonesia, Malaysia, Singapore, and the Philippines. The group officially named itself Jemaah Islamiah around that time period.
In the mid and late 1980s, many members of JI, including Sungkar and Hambali (see below) joined the Mujahideen in the resistance movement against the Soviet occupation of Afghanistan. They were joined by radical Muslims from extremist groups worldwide. Many of the connections that define the global network of Islamist groups that exists today, including those between al-Qaeda and JI, were made during the conflict in Afghanistan.
Back in Southeast Asia, the members of JI distributed pamphlets. Bashir preached jihad but he would do very little violent action. This changed in the 1990s. Bashir met Riduan Isamuddin, a.k.a. Hambali sometime in the early 1990s at a religious school that Bashir set up. Bashir became the spiritual leader of the organization while Hambali became the military leader. Hambali wanted a large Islamic caliphate to be established across Southeast Asia, incorporating Indonesia, Malaysia, Singapore, Thailand, the Philippines, Brunei, and Cambodia.
JI first formed itself into a group of terrorist cells that provided financial and logistical support when needed, to Al-Qaida operations in Southeast Asia. Hambali formed a front company called Konsojaya to help launder money to such plots, including the Operation Bojinka plot, which was foiled on January 6, 1995. The leaders of JI went back to Indonesia in 1998, when Suharto’s government was toppled. Hambali went underground while Bashir publicly promoted jihad.
In January 2000 cleric Hambali, al-Qaeda’s key representative in Indonesia, hosted in Malaysia Nawaf Alhazmi and Khalid al-Midhar, who would later take part in the September 11, 2001 attacks as hijackers. Unlike the Al-Mau’nah group, Jemaah Islamiah kept a low profile in Malaysia and their existence was publicized only after the 2002 Bali bombings.
In 2003 Indonesian police confirmed ‘the existence of Mantiqe IV “-the JI regional cell” which covers Irian Jaya and Australia.” Indonesian police saya Muklas has identified Mantiqe IV’s leader as Abdul Rahim -an Indonesian born Australian’.
Indonesian investigators revealed the JI’s establishment of an assassination squad in April 2007, which was established to target top leaders who oppose the group’s objectives, as well as other officials, including police officers, government prosecutors and judges handling terrorism-related cases.
In April 2008, the South Jakarta District Court declared JI an illegal organisation when sentencing former leader Zarkasih and military commander Abu Dujana to 15 years on terrorism charges.
Jemaah Islamiyah is reportedly allied with the Islamic Circle of North America (ICNA) in the United States.
* August 1, 2000 Jemaah Islamiah attempted to assassinate the Philippine ambassador to Indonesia, Leonides Caday. The bomb detonated as his car entered his official residence in central Jakarta killing two people and injuring 21 including the Ambassador.
* September 13, 2000 a car bomb explosion tore through a packed parking deck beneath the Jakarta Stock Exchange building killing 15 people and injuring 20.
* December 24, 2000 JI took part in a major coordinated terror strike, the Christmas Eve 2000 bombings.
* December 30, 2000 a series of bombings that occurred around Metro Manila in the Philippines, 22 died and over a hundred were injured. In the following years, several members of the Jemaah Islamiah for their suspected involvement in the bombings.
* March 12, 2002 3 JI members are arrested in Manila carrying plastic explosives in their luggage. One of them is later jailed for 17 years.
* June 5, 2002 Indonesian authorities arrest Kuwaiti Omar al-Faruq. Handed over to the U.S. authorities, he subsequently confesses he is a senior al-Qaeda operative sent to Southeast Asia to orchestrate attacks against US interests. He reveals to investigators detailed plans of a new terror spree in Southeast Asia.
* After many warnings by US authorities of a credible terrorist threat in Jakarta, on September 23, 2002 a grenade explodes in a car near the residence of a US embassy official in Jakarta, killing one of the attackers.
* September 26, 2002 the US State Department issued a travel warning urging Americans and other Westerners in Indonesia to avoid locations such as bars, restaurants and tourist areas.
* October 2, 2002 a US Soldier and two Filipinos are killed in a JI nail-bomb attack outside a bar in the southern Philippine city of Zamboanga
* October 10, 2002 a bomb rips through a bus terminal in the southern Philippine city of Kidapawan, killing six people and injuring 24. On the same day The US ambassador in Jakarta, Ralph Boyce, personally delivers to the Indonesian President a message of growing concern that Americans could become targets of terrorist actions in her country.
* October 12, 2002 On the second anniversary of the USS Cole bombing in Yemen, a huge car bomb kills more than 202 and injures 300 on the Indonesian resort island of Bali. Most are foreigners, mainly Australian tourists. It is preceded by a blast at the US consulate in nearby Denpasar. The attack known as the 2002 Bali Bombing is the most deadly attack executed by JI to date.
* Bashir was arrested by the Indonesian police and was given a light sentence for treason.
* Hambali was arrested in Thailand on August 11, 2003 and is currently in prison in Jordan, according to Haaretz.
* A bomb manual published by the Jemaah Islamiah was used in the 2002 Bali terrorist bombing and the 2003 JW Marriott hotel bombing.
* A British-born Australian named Jack Roche confessed to being part of a JI plot to blow up the Israeli Embassy in Canberra, Australia on 28 May 2004. He was sentenced to 9 years in prison on 31 May. The man admitted to meeting figures like Osama bin Laden in Afghanistan.
* JI are widely suspected of being responsible for the bombing outside the Australian embassy in Jakarta on 9 Sep 2004 which killed 11 Indonesians and wounded over 160 more.
* They are also suspected of committing the October 1st 2005 Bali bombings.
* November 9, 2005, bomb-making expert and influential figure in Indonesian terrorist organization, Azahari Husin was killed in a raid at Malang, East Java.
* August 5, 2006, Al-Qaeda’s Al Zawahiri appeared on a recorded video announcing that JI and Al-Qaeda had joined forces and that the two groups will form “one line, facing its enemies.”
* June 13, 2007 Abu Dujana, the head of JI’s military operations, is captured by Indonesian police.
* June 15, 2007 Indonesian Police announced the capture of Zarkasih, who was leading Jemaah Islamiah since the capture of Hambali. Zarkasih is believe to be the emir of JI.  * February 27, 2008 The leader of JI in Singapore, Mas Selamat Kastari, escaped from the Whitley Road Detention Centre at 1605 hours, local time.  * April 1, 2009 Mas Selamat Kastari was recaptured in Johor, Malaysia. * July 17, 2009 Jemaah Islamiah blamed for attacks on the Ritz Carlton Jakarta and the J.W. Marriott hotels in Jakarta.  * September 17, 2009, Noordin Top was killed in a raid by Indonesian police in Solo, Central Java. Top was a recruiter, bomb maker, and explosions expert for Jemaah Islamiyah. However, later on his colleagues in Jemaah Islamiah claimed that Noordin had formed his own splinter cell which was even more violent and militant. He was for a while dubbed the ‘most wanted Islamic militant in South East Asia’.
* March 9 2010,Dulmatin was killed in a raid by Detasemen khusus 88 in Pamulang. South Jakarta
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