Indonesian police said on Thursday they will re-arrest Muslim cleric Abu Bakar Bashir, the alleged leader of the Jemaah Islamiyah group, after he is released from prison on Friday.
"We will detain him. Investigators have concluded that information indicates that Abu Bakar Bashir was involved in crimes of terrorism," said police spokesman Basyir Barmawi.
"After he is released on April 30 he will certainly be detained."
The announcement set the stage for a potentially violent confrontation between police and Bashir's supporters, who have gathered outside Jakarta's Salemba jail where he is being held for immigration offences and forging documents.
Some 500 supporters from the Central Java city of Solo are on the way to Jakarta in addition to those already outside the jail, local radio said.
"We predict that tomorrow if (Bashir) is grabbed by police, blood will flow," Akhmad Khalid, one of his lawyers, told reporters.
Barmawi said police have new evidence that Bashir was "emir," or leader, of Jemaah Islamiyah (JI).
The spokesman said Bashir, 65, oversaw a ceremony in 2000 at the Hudaibiyah military academy run by JI in the southern Philippines in his capacity as emir.
He said there was also evidence that Bashir had sworn in Nashir bin Abbas as a regional head of JI in 2002 at Solo.
Barmwai said evidence includes a letter sent by an alleged JI leader, Mustafa, to "Abdus Samad," addressing him as the JI emir. Abdus Samad is one of Bashir's aliases.
Asked if Bashir would be charged with the Bali or Marriott bombings, Barmawi said: "There are no such partial charges."
"Of course I will resist my arrest within my capability but I do not like violence and I will fight with words and law," Bashir told reporters inside the prison.
"I cannot accept the action of the police because they serve the interests of foreigners, America and their allies. On this matter, America is intervening in Indonesia's sovereignty," the Muslic cleric said.
Hard-line and some mainstream Islamic groups also accuse Jakarta of bowing to US pressure.
The US and other foreign governments insist that Bashir led JI. US Homeland Security Secretary Tom Ridge said during a visit last month that Bashir was deeply involved in planning and carrying out terrorist acts.
Indonesian prosecutors have so far failed to convict him on this.