Before he was restrained by members of the congregation, the man managed to take an axe from the backpack and attacked the Rev. Albert Pandiangan, causing a slight injury to the 60-year-old priest's hand, Amar said.

The 18-year-old assailant left a bench and ran toward the priest at the altar, but a bomb in his backpack only burned without exploding, said national police spokesman Major General Boy Rafli Amar.

JAKARTA, Indonesia — A would-be suicide bomber's explosives failed to detonate in a packed church in western Indonesia during Sunday Mass, and he injured a priest with an axe before being restrained, police said.


The motive for the attack at the Roman Catholic St. Yoseph Church in Medan, the capital of North Sumatra province, was not clear, but the perpetrator carried a symbol indicating support for the Islamic State.

Police were interrogating the man, who told them he was not working alone, Amar said, without providing details.

Indonesia, the world's most populous Muslim nation, has carried out a sustained crackdown on militant networks since the 2002 bombings on the island of Bali that killed 202 people.

Almost all of Indonesia's roughly 250 million people are moderate Sunni Muslims, though there is a significant Christian minority. Compared with other large Muslim countries, militancy is relatively rare in Indonesia, though extremist groups have carried out minor attacks, including of churches.

The biggest attack occurred when terrorists bombed nightclubs on Bali, killing 202, including 88 Australians. Since then, the government has carried out a massive crackdown on militant cells.

The incident at Medan, Indonesia's third-largest city, marks the second Islamic State-inspired attack in the country this year. The militants have called on supporters worldwide to carry out attacks at home, rather than join the group in Syria, Iraq, and Libya.