The killing of five Al-Qaeda suspects including an Indonesian in southern Yemen this month has turned the spotlight on Indonesian students studying abroad in Yemen, and the possibility that students could become radicalised during their time there.
In just over a decade the number of Indonesian students studying in Yemen has grown from just a few hundred to some 2,000. The number is estimated variously from 1,500, considered a low estimate, up to 2,200 Indonesian students in the country.
Reports last year suggested that Indonesians returning home after studying in Yemen were being monitored as a possible security threat by the Indonesian authorities after suicide bombings at two luxury hotels in Jakarta in July 2009. Militants detained in connection with the bombings included at least one trained in Yemen.
Indonesian government officials said the potential for extremists coming from Yemen was "significant" because of the large number of Indonesian students there.
The fear is that this could spearhead an extremist movement that could spread from Indonesia to other countries in South East Asia.
Possible links were also highlighted during the trial and jailing in June this year of Indonesian Abu Wakar Bashiir, considered the spiritual leader of the shadowy Jemaah Islamiah movement, sometimes described as a South East Asian Al Qaeda offshoot. He was previously linked to the 2005 Bali bombings, although the charges against him were quashed by a supreme court ruling.
Concern about Yemen
Western security agencies have been turning their sights on Yemen in recent years, in particular on Al Qaeda in the Arab peninsula (AQAP) which, as a result of student-led unrest against President Ali Abdullah Saleh and resulting chaos, have been able to strengthen their presence in the south and east of Yemen.
"Yemen is becoming an important centre for terrorism activities both within its region and internationally" said Anthony Bubalo, director of the West Asia programme at the Lowy Institute based in Sydney, Australia.
"Students have been an important vector for the introduction of Islamic and Islamist ideas into Indonesia, including extremist ones," he added.
While Indonesian students abroad could come in contact with extremist ideas or activities in other countries in the Middle East or South Asia, countries like Yemen and Pakistan are both seen as important 'nodes' for international extremist activity, according to Bubalo.
Research published in September by the Lowy Institute in collaboration with the University of Western Australia's Centre for Muslim States and Societies and the University of Sydney's Centre for International Security Studies, found that in Yemen "the bulk of the Indonesian student population - over three quarters - attends well-established Islamic educational institutions with a mainstream religious outlook".
However, around a quarter of the Indonesian students in Yemen attend Salafi institutions, which "raises a number of risks in terms of potential extremist connections," according to the report Talib or Taliban? Indonesian students in Pakistan and Yemen.
"Salafi institutions teach a harder line version of Islam and share some ideas with violent extremists," said Bubalo. "Some Yemeni and international extremists have been graduates or students at some of the Salafi institutions that Indonesians attend."
Of some concern was the relative geographic isolation of the Salafi institutions, some of them in conflict areas in Yemen, "as a result of which some students were being provided with weapons training", the researchers said, adding that a number of Yemeni and international extremists had either been graduates or one-time students of these institutions.
Drop in students to Pakistan
Indonesian students study Islamic studies in a number of countries, including Egypt, Saudi Arabia, Syria, Sudan and Pakistan.
They study abroad for a variety of reasons, the report said, often "simply following a practice throughout the Islamic world whereby students study at Islam's more prestigious centres of higher learning such al-Azhar in Egypt".
However, the number of Indonesian students going to Pakistan has dropped dramatically, particularly to the most hard-line institutions, according to Bubalo.
This is in part due to tighter visa restrictions in Pakistan. Indonesian students typically have to wait several weeks for a visa to study in Pakistan since and those applying to religious institutions require clearance from the Pakistani ministry of the interior, which in turn consults other intelligence agencies.
Nonetheless, "efforts by Indonesian extremists to get to Pakistan continue and the prospect that these students will try to use student cover is very real," Bubalo said.
Historic links with Yemen
In contrast with the difficulties in applying to institutions in Pakistan, a number of Yemeni universities now have branch offices in Indonesia to help facilitate student travel to Yemen.
Many went to Yemen because the quality of Islamic education there is seen by Indonesian students as very rigorous, with high standards and tough exams.
The largest concentration of students, up to three quarters of all Indonesian students in Yemen, are in the Hadhramaut governate, particularly the city of Tarim, where there are four large Islamic institutions regarded as mainstream universities, including one for women.
Indonesia has historic relationship with that region of Yemen, going back centuries through ancient trade routes.
"A common theme among the Indonesian students interviewed was how Yemen reflected an attractive mix of exotic locale but culturally familiar Islam," the researchers said.
They emphasised that not all Indonesian students in Yemen were potential terrorists. "Indonesian students are less likely to be radicalised in Yemen than they are to go there with extreme or radical views already formed," the report said.
It stressed that the research did not identify significant evidence of direct contacts between Indonesian and Yemeni extremists via student channels.
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