The Jemaah Ansharut Daulah (JAD) terrorist group in Indonesia and two of the country's more prominent militants have been placed on a US counter-terrorism watchlist because of their ISIS ties.
The move, which opens the way for US enforcement action against them, comes amid the growing threat in South-east Asia of the Islamic State in Iraq and Syria (ISIS) as it continues to lose ground in the Middle East to coalition forces.
In a statement on Tuesday, the US State Department said JAD, which was behind a brazen attack in Jakarta last January, has been marked as a "Specially Designated Global Terrorist" group.
"JAD is a terrorist group based in Indonesia that was formed in 2015 and is composed of almost two dozen Indonesian extremist groups that pledged allegiance to (ISIS) leader Abu Bakr al-Baghdadi," said the State Department.
Separately, the US Treasury said on the same day that Indonesians Aman Abdurrahman and Bahrumsyah have been added to its "Specially Designated Nationals" (SDN) list, due to their links to terrorism.
This also means their assets are blocked, and American companies and individuals are prohibited from having dealings with them.
Bahrumsyah is believed to be in Syria, where he has been appointed by Baghdadi to lead a battalion of foreign fighters from South-east Asia who had joined ISIS in the Middle East. Aman is said to have ordered the attack last Jan 14 in Jakarta - which killed eight people, including the four perpetrators - from inside Indonesia's maximum- security Nusakambangan prison.
He is also purportedly the leader of JAD, an offshoot of the Jemaah Islamiah terror network led by Abu Bakar Bashir.
Other Indonesian militants sanctioned by the United States and placed on the terrorist watchlist include Bashir, who is in jail; former Al-Qaeda leader Hambali, who has been held at Guantanamo Bay for the past 10 years; and Santoso, leader of the Mujaheedin Indonesia Timur.
Santoso, once the country's most wanted terrorist, was shot dead by Indonesian security forces while he was on the run in Poso, Central Sulawesi, last year.
The Indonesian police's primary counter-terrorism force Detachment 88 (Densus 88) has been largely effective, thwarting as many as 15 terror plots, including one against Singapore, recently.
Densus 88 also arrested more than 150 suspects and uncovered new tactics such as the use of women as suicide bombers by local terrorist cells last year.
But the Indonesian authorities are still unable to prosecute more than 50 citizens who have returned home after joining ISIS in the Middle East, because of weak anti-terror laws in the country.
Parliament is set to continue its deliberation on proposed revisions to a Bill to grant the police more powers to detain terror suspects, particularly ISIS returnees, for investigation.
Meanwhile, the country remains on high alert as it approaches the first anniversary of the Jan 14 attack in Jakarta on Saturday.
Besides Aman and Bahrumsyah, the US Treasury Department on Tuesday also put Australians Khaled Sharrouf and Neil Prakash, as well as British national Alexanda Amon Kotey, on the SDN list.
Prakash, one of Australia's most wanted terrorists, is an ISIS recruiter, while Kotey is one of four members of an ISIS cell that was behind the beheadings of 24 hostages.