Australian police say a knife attack in Sydney that wounded a bishop and a priest during a church service as horrified worshippers watched online and in person, and sparked a riot was an act of terrorism. Police arrested a 16-year-old boy Tuesday after the stabbing at Christ the Good Shepherd Church that injured Bishop Mar Mari Emmanuel and a priest. Both are expected to survive.

New South Wales Police Commissioner Karen Webb said the suspect’s comments pointed to a religious motive for the attack. “We’ll allege there’s a degree of premeditation on the basis that this person has travelled to that location, which is not near his residential address, he has travelled with a knife and subsequently the bishop and the priest have been stabbed,” Webb said. “They’re lucky to be alive.”