The alleged planner of the brazen attack in Jakarta on Thursday (Jan 14) is believed to be Indonesian militant Muhammad Bahrun Naim, a leader of militant group Katibah Nusantara.
He is said to be in the Syrian city of Raqqa, the de facto capital of the Islamic State in Iraq and Syria (ISIS) after the militants seized it in late 2013.
Here are eight things to know about Muhammad Bahrun Naim:
1. He used to be a computer technician
Reports said he used to work as a computer technician and ran an Internet cafe in Surakarta. He is believed to be from Pekalongan in Central Java.
2. He spent time in an Indonesian jail
He was arrested in November 2010 by the Indonesian police's elite counter-terrorism unit Detachment 88. They confiscated hundreds of bullets from his home and he was sentenced to two and a half years in prison in 2011 for illegal possession of ammunition. But the court found insufficient evidence to pursue terror charges. He disappeared after he had served his time and police believed he moved to Syria.
3. He aims to become ISIS' "leader" in this region
Naim is a leader of Katibah Nusantara, which is a South-east Asian military unit under the ISIS that recruits militants from Indonesia, Malaysia and other parts of the region.
In April 2015, Katibah Nusantara fighters captured territory held by Kurdish forces in Syria, which was a boon for its online drive to recruit new fighters and supporters among Malay speakers in South-east Asia, according to a research paper published last year by the S. Rajaratnam School of International Studies in Singapore. Jakarta Police Chief Tito Karnavian said Naim clearly has ambitions to become "the leader" of ISIS in this region.
4. He runs a blog
He has a blog which hails attacks carried out by affiliates of ISIS, and offers encouragement and advice to those who have declared allegiance to the militant group.
For example, there were many posts containing information on building explosives.
5. He learnt lessons from Paris attacks
After the terror attacks in Paris in November 2015, Naim published a blog post titled "Lessons from the Paris Attacks" in which he urged his Indonesian supporters to study the planning, targeting, timing, coordination, security and courage of the Paris militants.
He also explained in his blog how easy it was to move jihad, or the holy war, from "guerrilla warfare" in Indonesia's jungles to a city.
6. 'Just waiting for the right trigger', he said of potential Indonesia attacks
Reuters news agency contacted him on Nov 24 on social messaging app Telegram, using details provided by one of his acquaintances.
In that exchange, he said there were more than enough ISIS supporters to "carry out an action" in Indonesia. "Just waiting for the right trigger," said the man identifying himself as Naim. Not long after that Telegram exchange, intelligence officials began to pick up talk in social messaging chatrooms that an attack on Indonesia was imminent.
7. He had been planning Jakarta attacks for a while
Indonesian police believed Naim had masterminded the Jakarta attack and had been "planning this for a while".
Police spokesman Anton Charliyan said he had even sent money back to Indonesia to finance the attack.
8. He has no plans to return to Indonesia
Naim reportedly has no plans to return to Indonesia.
In the same Telegram exchange with Reuters, he said he enjoyed life in Syria and did not plan to return home. "I move around, depending on where our emir orders us to go. It's good here in Syria. There's electricity, accommodation, water and it's free. The services provided by them are good, cheaper than in Indonesia," he said.
SOURCES: REUTERS, AFP, BBC