JAKARTA (AFP) - Indonesia could help combat the threat of homegrown extremism by banning its citizens from travelling abroad to fight with organisations such as the Islamic State group, a think-tank said on Monday.
The Jakarta-based Institute for Policy Analysis of Conflict (IPAC) said new laws banning any involvement with foreign militant 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 militants, 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, 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 organisations 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 offences, 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 offences 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.