Police say children radicalised by parents to help carry out spate of suicide attacks in East Java

This article is more than 2 years old

This article is more than 2 years old

The families behind a wave of suicide bombings in the Indonesian city of Surabaya were all members of the same religious study group who radicalised some of their children through homeschooling, investigators in East Java have said.

Ch Insp Machfud Arifin said the three families were all connected through a Sunday evening group, adding that they met each week to study Islam and watch jihadist films.

The content of the films included footage from Syria and Iraq, as well as Isis attacks in France, and was intended to encourage those in the group to commit terrorist attacks, he said.

“The Surabaya cell and the Sidoarjo cell are the same network because they met regularly on Sunday evening,” said Arifin, referring to the three families behind the attacks.

Play Video 0:27 Three churches in Indonesia hit by suicide bombers – video report

The study group met at the Surabaya home of Dita Oepriarto, the father of a family of six that targeted three churches in coordinated suicide bombings just before services began on Sunday morning, police said.

Oepriarto, his wife, Puji, and their four children, the youngest, a daughter aged nine, carried out the deadly strikes.

Speaking on Tuesday, Arifin said some of the children of the three families had been homeschooled as a way to radicalise and insulate them from outside ideas.

“What happened is their parents indoctrinated the children,” said Arifin, “So when the mother asked them to wear the waist bombs they did it.”

At least 26 people were killed and dozens more injured in the multiple suicide bombings, the deadliest terrorist strike in Indonesia in more than a decade. Of those killed, 13 were the perpetrators.

The first attack targeted three churches early on Sunday morning. Later that evening there was multiple explosions in a flat in Sidoarjo, less than 12 miles from Surabaya. The authorities believe the blasts were from bombs exploding prematurely.

Police said they uncovered the link between the three families through interviews with the surviving children of the Sidoarjo family.

On Monday morning a family of five also bombed the Surabaya police headquarters. Using two motorbikes, they drove into the carpark where they detonated their waist bombs. An eight-year-old girl is the only surviving family member.

All perpetrators in both the church bombings and police station attack had their national identification cards on them. Police said it was as though they wanted to be easily identifiable.

The three families are believed to members of the pro-Isis Indonesian militant group, Jamaah Ansharut Daulah (JAD).

Oepriarto was the head of the Surabaya extremist group.

Police said they were hunting for two senior JAD members in East Java.