Jakarta. Two suicide bombers who launched Sunday's attack on a catholic church in Makassar, South Sulawesi have been identified as a married couple, police said on Monday. 

The attack injured at least 20 people and instantly killed the bombers.

"They were married just six months ago," National Police Chief Listyo Sigit Prabowo said in a statement on Monday. 

They came to Katedral Church in Makassar on a scooter driven by the husband, who was identified only by initial L.

Listyo said the couple belonged to homegrown terror network Jamaah Ansharut Daulah (JAD), which he said took part in another church bombing in the Philippines in 2018.

The United States government designated JAD a terrorist organization in January 2017, in a move to disrupt Islamic State operations in Southeast Asia.

Listyo said the male bomber had written a farewell letter to his parents prior to the attack, saying he would carry out jihad.

"The woman has been identified as Y.S.F. based on the fingerprint recognition process," the police chief added.

Police searched a leased house in Bontoala district, Makassar where the couple lived before carrying out the attack. They also searched the home of the male bomber's parents only 50 meters from the leased house.

It's not the first time married couple or even the whole family took part in terror attacks, the infamy that now goes with the JAD.

In October 2019, a couple waited and approached the entourage of then Chief Security Minister Wiranto and the husband suddenly attacked and injured the minister with a knife.

In May 2018, the country was rocked by coordinated attacks on three churches in Surabaya, East Java by parents and their four young children. Following the horrifying attacks, the South Jakarta District Court declared JAD an organization committed to acts of terror, with proven ties to the radical Islamic State group, and ordered its immediate disbandment under the 2002 Anti-Terrorism Law. 

The shadowy group has been the most active of its kind in Indonesia over the past few years, and it is believed to have been behind the terror attack in Jalan Thamrin in Central Jakarta in January 2016, a church bombing in Samarinda, East Kalimantan, in November 2016, a suicide bombing at a bus shelter in Kampung Melayu, East Jakarta, in May 2017, and armed assaults on policemen in Bima, West Nusa Tenggara, in September 2017.

State prosecutors told the court that JAD was founded by terror convict Aman Abdurrahman in October 2014, while imprisoned on Nusakambangan Island in Central Java. It also emerged that the group's members had pledged allegiance to Abu Bakar Al Baghdadi, the leader of Islamic State.

Crackdown
At least 13 suspects were arrested in a major crackdown on terrorism across the country following the Sunday's church bombing.

Police said they have arrested four suspects in South Sulawesi, another four in Greater Jakarta and five in West Nusa Tenggara in the past 24 hours.

During raids in East Jakarta and neighboring Bekasi, police discovered five explosive devices and bomb materials weighing 4 kilograms, Listyo said.