Indonesian police stand guard outside house of suspected terrorist (file)
Indonesian police stand guard outside house of suspected terrorist (file)Reuters

Indonesia could help combat the threat of homegrown extremism by banning its citizens from travelling abroad to fight with terrorist organizations such as the Islamic State (ISIS), a think-tank said Monday.

The Jakarta-based Institute for Policy Analysis of Conflict (IPAC) said new laws banning any involvement with foreign terrorist groups overseas were necessary to help stem the flow of fighters from Indonesia to battlegrounds in the Middle East.

More than 500 Indonesians have gone to Syria and Iraq to fight alongside ISIS terrorists, according to the country's counter-terror chief, prompting President Joko Widodo to consider new measures to combat the threat of homegrown radicalism.

Indonesia, the world's most populous Muslim-majority nation with has a population of over 250 million, has already banned support for ISIS and its ideology.

But in its latest report, IPAC said police efforts to prevent future jihadists from travelling to Syria and Iraq would continue to face hurdles without appropriate legislation.

"As long as joining foreign military or terrorist organizations is not a crime, it is difficult to prosecute," the report said.

There are concerns internationally about the impending release from Indonesian jails this year and next of 130 inmates convicted of terrorism offenses, a fear exacerbated by the presence of former prisoners among Indonesia's ISIS ranks.

Though IPAC found only a minority of the 270 people convicted of terror offenses in Indonesian jails supported ISIS, it said some more extreme prisoners maintained strong links to outside groups and posed a serious threat.

Indonesia's most notorious radical cleric Abu Bakar Bashir swore allegiance to ISIS along with 23 other inmates at a Java prison in July.

Widodo is reportedly considering revoking the passports of Indonesians who have left for Syria, and is exploring other ways of charging those trying to join ISIS.

Indonesia has waged a crackdown on extremist groups for more than a decade following attacks against Western targets including the 2002 Bali bombings - a campaign that has been credited with weakening key networks.

There are fears that fighters returning from Iraq or Syria could revive these networks.

ISIS is not the only terrorist organization that has turned its eyes on Indonesia; last month the Gaza-based terrorist organization Hamas sought to open an official office in Indonesia to manage its ties and fund-raising in the Far East.

Hamas's request was denied, although Indonesia's Foreign Ministry director general for multilateral affairs Hasan Kleib said "Indonesia does not differentiate between factions in Palestine. The Embassy of Palestine in Jakarta represents all the people of Palestine." The statement indicates the open stance regarding Hamas.

Indonesia has recognized the "state of Palestine" since 1988.

AFP contributed to this report.