The brother of Jemaah Islamiyah's (JI) alleged master planner Hambali is proving hard to crack, Pakistani intelligence said today, as Malaysia alleged 13 students arrested with him were being trained as future JI leaders.

Malaysia's Deputy Home Minister Chor Chee Heung said in Kuala Lumpur that the 13 Malaysians, arrested with six Indonesians from Islamic seminaries in Karachi, were being groomed to lead the al Qaeda-linked Southeast Asian terror network.

They had already undergone training at a Malaysian Islamic school formerly run by senior JI figures, and some were children of JI members in Malaysia, state media quoted the minister as saying.

Pakistan has called the 19 Southeast Asian students, including Hambali's brother Rusman Gunawan, a JI sleeper cell and a potential "second generation of JI terrorists."

"We feel we have been able to nip evil in the bud by capturing a would-be second generation of JI's group of terrorists," said Pakistan's Interior Minister Faisal Saleh Hayat.

Hard to break

Pakistani investigators are questioning them on possible future attack plans and hitlists.

"Rusman Gunawan is hard to break. He's come out much tougher than his baby-faced appearance," said an official who was involved in his arrest.

"It took two days before he started speaking, but even then there were a lot of contradictions in his statements."

Material recovered from the students, including computer disks and mobile phones, showed they were being groomed for future operations, an Islamabad-based security official said.

"The computer disks had recorded lectures highlighting the virtues of jihad against anti-Islam forces and the duty of all Muslims to strike terror in the hearts and minds of infidels (non-Muslims)," the official, who could not be named, told AFP .

"We are now intensively interrogating them on whether they had targets or a hitlist here or outside Pakistan."

Gunawan was arrested from the Abu Bakar University in this port city of 14 million people on Sept 1 following a tip-off from US investigators interrogating Hambali, who has been in US custody at a secret location since his capture in Thailand on Aug 11.

Gunawan's capture led to the arrests of the other 18 students.

Four investigators dispatched

Hambali is considered al-Qaeda's pointman in Asia and operations of chief of JI, which is blamed for the October Bali bombings that killed 202 people and a string of other deadly bombings.

Indonesia is sending four investigators to Karachi on Saturday to question its six detained nationals incluing Gunawan.

"We wish to be informed by the Pakistani government about the nature of the allegations made against these individuals and how they may relate to Indonesia," a spokesman said in Jakarta today.

Gunawan, who has been praying five times a day in his cell, has denied links to JI, but speaks with admiration for the group when asked about it, the intelligence official said.

"He thinks highly of the movement. He smiled when asked about jihad (holy war)," the official said.

Speaking through an interpreter, the student has refused to answer questions about Hambali or other members of his family.

The official said Gunawan had overstayed his visa to study in Pakistan by three years.

Islamabad plans to deport the 19 students but wants to complete its investigations first.

Another intelligence official said it was unlikely the group would be prosecuted in Pakistan.

"I don't think any of them will be prosecuted here, but what we are trying to find out about is their terrorist plans. These are sensitive matters," he said.

Authorities are investigating whether the alleged sleeper cell extended to religious schools in North West Frontier Province bordering Afghanistan, he said. - AFP