Indonesian police have not found the rocket that the leader of a Batam terror cell had wanted to fire at Singapore's Marina Bay, but said the men had training in handling firearms and had also set up a command structure.
Riau Islands police chief Sam Budigusdian told reporters in Batam yesterday that preliminary investigations showed that Katibah GR - or "Cell GR" - led by Gigih Rahmat Dewa had conducted "routine firearms training" in the forests of Nongsa, in northern Batam.
Six suspects from the little- known group were arrested in an anti-terror swoop last Friday. One of them, 19-year-old Muhammad Tegar Sucianto, has since been released as police did not find any evidence linking him to the cell.
General Sam said that the members each had a specific role.
Gigih, a 31-year-old factory worker, was the "amir", or commander.
Trio Syafrido, 46, acted as the "field coordinator", Hadi Gusti Yanda, 20, was the "treasurer", while Eka Saputra, 35, and Tarmidzi, 21, were "weapon assemblers".
General Sam said the police were still studying how far the plan to attack Singapore had progressed.
"The order for the attack could well have been given to this group in Batam, but it could be carried out by other groups."
He added that the Singapore authorities "have requested cooperation with Indonesian police to uncover the network" to maintain security in the region.
In Jakarta, national police spokesman Boy Rafli Amar said yesterday that "no physical rocket or bomb" had been found, only bomb-making materials.
However, he warned against underestimating the group, which has been active for about two years.
The cell members, he said, had received "online training" to build the rocket from Indonesian militant Bahrun Naim.
Bahrun fled the country last year and is now believed to be fighting alongside the Islamic State in Iraq and Syria (ISIS) in Syria.
"They are ISIS. They are ISIS sympathisers and, since they are affiliated with Bahrun Naim, they are clearly related to ISIS," Mr Boy Rafli added.
He said Bahrun had used Facebook chats to rally Indonesians to join the battle in Syria, recruit cell members and send "instructions long-distance".
Bahrun also used social media to teach them "how to carry out terror attacks, assemble firearms, make explosives, and build that rocket".
"We are now trying to confirm if they had built the explosives for the attack... on Marina Bay Singapore, like they had planned through their electronic communication," Mr Boy Rafli added.
The five men remain in police custody in Batam for questioning, and will be taken to Jakarta later.
Batam police are carrying out more raids on the group's "safe houses", and are also trying to determine the extent of Gigih's network.
Correction note: In an earlier version of the story, we referred to Riau Islands police chief as Sambudi Gusdian. His name should be Sam Budigusdian. We are sorry for the error.
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