Bali, Indonesia ? Police pursued a tip Wednesday from a caller claiming that one of the latest Bali suicide bombers studied on an Indonesian island known for having hard-line Islamic schools.

It was one of the few possible leads announced since police started circulating nationwide photographs of the three bombers’ severed heads, recovered from the attacks Saturday on crowded tourist-resort restaurants. The blasts killed 22 and injured 104.

The tipster called police in Solo, a city on the main island of Java. He identified one of the bombers by name and said he had studied in the area, home to an radical Islamic boarding school attended by several militants convicted in previous terror attacks, said Abdul Madjid, Solo’s police chief commissioner. He gave no further information.

The al-Qaida-linked Jemaah Islamiya was emerging as the key suspect in Saturday’s attacks, which came three years after Bali nightclub bombings that killed 202 people, blamed on the regional Islamic extremist group.