Indonesian police said they have arrested 13 suspects in connection with the suicide bomb attack by a husband and wife outside a Roman Catholic church on Sulawesi Island on Sunday, with bombs and explosive materials confiscated.

The husband and wife were members of the extremist Jamaah Ansharut Daulah group, which was involved in the bombing of a cathedral on Jolo Island in the southern Philippines in January 2019 that killed 23 people, the police said.

Police officers stand guard in front of a church in Makassar, South Sulawesi Province, Indonesia, after a suicide bomb attack there on March 28, 2021. (Anadolu Agency/Getty/Kyodo)

At least 20 people were injured in the explosion that occurred when the two rode a motorcycle into the vicinity of the Most Sacred Heart of Jesus Cathedral in Makassar, the capital of South Sulawesi Province.

National Police Chief Listyo Sigit Prabowo told reporters that the 13 suspects had been arrested in Makassar, Jakarta and in the town of Bima in eastern Indonesia.

Listyo said the suspects seemed to have different roles in the group, such as indoctrinating new members and buying materials for making suicide bombs.

Earlier Monday, counterterrorism police raided a used car showroom in East Jakarta and a bicycle repair shop in the nearby town of Bekasi, in which they seized five active bombs and 5.5 kilograms of powerful explosive materials.

The Sunday explosion came just after a Palm Sunday Mass with churchgoers and church security guards among the injured.

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