As a crackdown on Islamic militants enters its third month, security forces have stepped up the manhunt in the thick jungles of Poso in Central Sulawesi where Indonesia's most wanted terrorist is thought to be hiding.
The joint operation between the national police, its elite Detachment 88 counter-terrorism unit and the Indonesian military has been ratcheted up in the past week as the task force believes they are closing in on members of local extremist group East Indonesia Mujahidin (MIT).
The high-value target, or HVT in military-speak, of the campaign is Abu Wardah, better known as Santoso, the leader of MIT, which has pledged its allegiance to the Islamic State in Iraq and Syria (ISIS).
Three Indonesians, suspected to be militants, were arrested over the weekend, The Jakarta Post reported yesterday.
It is not yet clear if the men were linked to the MIT.
They were nabbed in separate raids near Parigi Moutong, a regency within Central Sulawesi, but Santoso remains at large.
Although the exact number of troops involved in the operation, code-named Camar Maleo IV, is kept secret for operational reasons, The Straits Times understands it has been running since September.
The Indonesian authorities say MIT has been operating out of Poso for some time now.
Several threats issued recently, including a nine-minute video on social media sites that called for strikes on the Jakarta police headquarters and the presidential palace last weekend, have been attributed to Santoso and the MIT.
Security was beefed up at various locations across the country last Saturday, including the presidential palace in Bogor, West Java, where President Joko Widodo attended an event in the city, just a two-hour drive from the capital Jakarta.
ISIS has reached out to militant elements in at least five Indonesian provinces - East Java, Lampung in Sumatra, South Sulawesi, West Sulawesi as well as Central Sulawesi - in recent years.
Police investigations and intelligence have uncovered funding and other support from ISIS reaching domestic extremist groups such as MIT.
The information was backed by the Indonesian Financial Transaction Reports and Analysis Centre (PPATK) which, in collaboration with its Australian counterpart, detected seven billion rupiah (S$700,000) in cash flowing into Indonesia to fund terrorism activities over the last three years.
PPATK deputy chief Agus Santoso said the money was used to finance military training, pay for arms and to compensate widows of the terrorists who died fighting for the cause.
Jakarta police chief Tito Karnavian, a former commander of Detachment 88, warned last week that Indonesia could become a host for ISIS in South-east Asia.
On Sunday, national police chief Badrodin Haiti said troops were also trying to flush out three foreign fighters believed to have been part of a gang of seven from the East Turkestan Islamic Movement, an Uighur separatist group based in the restive Xinjiang region in China.
Four of the same group were arrested last year before they could link up with Santoso, while the three at large are said to have joined the MIT in the Poso jungles.
"They are understood to be in the same location as Santoso, namely in the jungles of Gunung Biru, where there are (militant) training camps, so they are fugitives like Santoso," said General Badrodin.