Jakarta. The bombing at a catholic church in the South Sulawesi capital on Sunday morning was carried out by two suicide bombers who died instantly at the scene, a top security minister said.

The attack injured at least 20 people, including churchgoers, security guards and bystanders, Coordinating Minister for Political, Legal and Security Affairs Mahfud MD said in a press conference in Jakarta.

“The casualties are the two persons who allegedly carried out the suicide bombing,” Mahfud said.

"The government has instructed the National Police and the Military to beef up security at worship places and public areas across Indonesia," Mahfud said.

"This is the act of terror. According to law, it’s a serious crime that undermines national ideology and security, human values and people’s lives," he added.

Footage from security camera nearby shows the explosion on a relatively quiet road in front of the church. It caused thick smoke and blaze and destroyed the rear of a passing car. 

At least four people can be seen walking out of a building into the sidewalk just when the bomb is about to explode.

The National Police said the attack could have claimed more lives without intervention by a church security guard.

The guard, identified only as Kosmas, prevented the bombers from entering the church yard, National Police spokesman Inp. Gen. Argo Yuwono said.
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The two bombers were on a scooter when carrying out the attack, he added.

Kosmas sustained injuries in his head and abdomen and is currently being treated at a police hospital in Makassar.

Ten hours after the attack near Katedral Church, police were still unable to identify any suspect. No group has claimed responsibility for the bombing.

The police weren’t able to confirm whether the bombers are men or women until the forensic team concludes identification process from the body parts retrieved at the scene, Argo said.