Jemaah Islamiyah (JI) is an Indonesia-based clandestine terrorist network established in the early 1990s. Its primary goal is to establish an Islamic state covering southern Thailand, Malaysia, Singapore, Indonesia, Brunei, and the southern Philippines. The network’s operatives received training in camps located in Afghanistan and the southern Philippines, and they began carrying out attacks in 1999.
The existence of JI came to light in late 2001 after Singaporean authorities thwarted a cell plan to attack targets associated with the US Navy. Subsequently, Southeast Asian governments took action, leading to the arrest of over 300 suspected terrorists, which significantly weakened JI’s network.
Despite the arrests, JI orchestrated a series of deadly bombings from 2000 to 2005, including the infamous 2002 Bali nightclub bombings that claimed 202 lives, the 2003 car bombing of the JW Marriott hotel in Jakarta resulting in 12 fatalities, the 2004 truck bombing of the Australian Embassy in Jakarta that killed 11, and the 2005 suicide bombings in Bali which killed 22 people.
A splinter group of JI led by Noordin Mat Top conducted suicide bombings at two hotels in Jakarta in July 2009. However, Indonesian police managed to neutralize Top in September of the same year.
Since 2009, JI’s prominence has waned due to the rise of splinter groups and other Indonesia-based terrorists. These factions consist of both experienced operatives formerly affiliated with JI and convicted terrorists who resumed their activities upon completing their prison sentences.
One such operative, Umar Patek, was arrested by Pakistani authorities in January 2011 and later convicted in June 2012 for his involvement in the 2002 Bali bombings. He was sentenced to 20 years in prison. In November 2012, Philippine security forces dealt a blow to JI by killing senior Indonesian JI leader Sanusi.
Despite the setbacks suffered by JI, the threat of terrorism in Southeast Asia persists, with governments remaining vigilant against the emergence of new extremist groups and the resurgence of established ones.
