Indonesian police have handed their file on the alleged leader of regional terrorist group Jemaah Islamiyah over prosecutors, bringing militant Islamic cleric Abu Bakar Bashir one step closer to prosecution. But legal technicalities will make any case hard for the prosecutors to win.

Police and foreign intelligence agencies believe that Abu Bakar Bashir was the leader of Jemaah Islamiyah. The group was behind both an October 2002 Bali nightclub bombing, which killed 202 people, and last August's Marriott Hotel bombing in Jakarta, in which 12 people died.

On Wednesday, police handed prosecutors the dossier containing their investigation into Mr. Bashir.

Wirawan Adnan is a member of Bashir's defense team, and says the accusations, particularly over the Marriott attack, are weak.

"He had been in detention for eight months when the Marriott bombing took place," said Wirawan Adnan.

Mr. Bashir denies being the leader of J.I. and being involved in terrorism, but many of the men who carried out the bombings were students at the Islamic boarding school he ran, and some of the Bali bombers implicated him during their trials.