JAKARTA- A prominent Islamic State figure in Indonesia, currently serving a nine-year prison sentence for terrorism, allegedly ordered accomplices to join IS-linked combatants in the southern Philippines, a local newspaper and police said Friday.

Aman Abdurrahman instructed members of Jamaah Ansharut Daulah, or JAD, an IS-linked group he set up, to join heavily-armed Maute group members in the southern Philippines town of Marawi as combatants, the Koran Tempo daily newspaper quoted National Counterterrorism Agency Chief Suhardi Alius as saying.

According to Suhardi, there are over 40 Indonesians fighters in the southern Philippines, 38 of them members of JAD, which the U.S. Department of State declared a terrorist organization in January.

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Aman has been jailed since December 2010 at the notorious Nusakambangan prison, dubbed as Indonesia's Alcatraz, for financing a Muslim militants training camp in Aceh Province, northern Sumatra.

"Aman indoctrinated them from prison," Suhardi said, adding that before leaving for Marawi, militants "visited Aman in prison."

Previously police said Aman has been held in an isolation cell since late 2016, making it unclear how followers could have visited Aman since then.

Aman allegedly delegated the JAD leadership to Zainal Anshori, who was arrested by counterterrorism police in April.

• READ: New air strike vs Maute rebels as officials vow to end Marawi siege

In a related development Tuesday, police arrested another militant, identified as Rochmat Septriyanto, in Yogyakarta Province for allegedly facilitating four Indonesians to travel to the Philippines to fight there. The four Indonesians have been put on a wanted list by the Philippine authorities.

National Police Spokesman Martinus Sitompul said Rochmat also had allegedly sent $7,500 to the Philippines.

Fighting between government forces and the IS-linked Maute group erupted May 23, when authorities tried to capture Isnilon Hapilon, a leader of the notoriously violent Abu Sayyaf rebel group, who was reported to be in Marawi for medical treatment.