Nurfika Osman & Farouk Arnaz – Despite the confirmed death of terrorist mastermind Dulmatin, a resurgent and expanding militant network still posed serious security concerns, experts warned on Wednesday.

Andi Widjajanto, a military analyst from the University of Indonesia, said regional terrorist group Jemaah Islamiyah, blamed for a string of deadly terrorist attacks including the 2002 Bali bombings, appeared to be growing stronger as it was now no longer solely based in Java.

"They are recruiting new members outside Java and developing new cells," he said. "We estimate that there are 300 active JI members spread nationwide with [an additional] 240 released terrorist convicts. This does not include many people who are being trained secretly."

National Police Chief Gen. Bambang Hendarso Danuri, addressing a news conference earlier on Wednesday, said JI was regrouping despite the fact police had killed or captured more than 400 terrorist suspects since 2002.

"JI always reorganizes itself," Bambang said. "We should remain alert to this threat even though we've already killed several of their leaders and captured more than 400 terror suspects."

Bambang said the police believed Dulmatin, who allegedly established a shadowy paramilitary training camp in Aceh, had encouraged raising funds by robbing non-Muslims. JI has in the past used armed robberies to fund its terrorist attacks.

Brig. Gen. Surya Dharma, the National Police's former antiterror chief, told the Jakarta Globe that the recent police raids on militants in Aceh and Java were proof that JI was still a presence and was changing its tactics.

He said police had been concerned for some time that JI would adopt the same tactics as Abu Sayyaf, a violent Muslim separatist group based in the southern Philippines, which favors kidnapping for ransom and hit-and-run attacks.

Those fears were heightened when it became apparent that Dulmatin, who is closely linked to Muslim separatist groups in the Philippines, returned to Indonesia, Surya said. Andi said Dulmatin's return was to fill the power vacuum left after JI's former leader, Noordin M Top, was killed last year.

But Noor Huda Ismail, head of the Institute for International Peacebuilding, said the peace deal struck between the Moro Islamic Liberation Front and the Philippine government was more likely to have prompted his return.

Meanwhile, Andi said three dangerous terrorist suspects still remained at large, namely Upik Lawangga, Umar Patek and Zulkarnaen.

Both Umar and Zulkarnean are wanted by the US government for their roles in the 2002 Bali bombings, while Zulkarnean is believed by some analysts to now head JI.

"Umar Patek is still on the run; we don't know where he is," Andi said. "The latest information has placed Zulkarnaen in Sabah, Malaysia. The third person is Upik Lawangga and he's believed to be in Poso, Central Sulawesi, developing a new group."

He said that JI had selected Aceh and other places off Java for its bases as part of a "new pattern of terrorism."

Aside from being a former conflict area, Aceh was also suitable as a base as it was near the Malacca Strait, providing a good vantage for both escape and spreading terrorism, Andi said.