A teenager, reportedly carrying a drawing of the ISIS flag, attacked a priest with an axe after the failed bid.
A police spokesman said the teen left a bench and ran towards the priest at the altar, but the homemade explosives only burned without detonating.
Before he was restrained by members of the congregation, the suspect managed to take an axe from his backpack and attack Priest Albert Pandiangan, causing a slight injury to the 60-year-old’s arm.
Local chief detective Nur Fallah said: “Somebody tried to kill the priest by pretending to attend the church service and at that time tried to explode something, like a firecracker, but the firecracker didn’t explode, it only fumed.”
Police have said the motive for the attack at the Roman Catholic St. Yoseph Church in Medan, is not clear. The teenager reportedly carried a drawing of an ISIS flag and his ID card.
Rina Sari Ginting, a spokeswoman for Medan police, said: “A terrorism act was carried out on Sunday morning at the Saint Joseph catholic church.
“Police are interrogating the perpetrator… and will search his house for any bomb-making materials.”
The suspect has reportedly told police he was not working alone.