New Zealand's Islamic community is shocked that a Christchurch teen was planning to ram a car into a group of people.

The teenager, who was sentenced at the Christchurch District Court yesterday, was radicalised online.

He had dropped out of school, converted to Islam, and had thought about killing people for five months.

He told police that he had 'done it for Allah'.

Federation of Islamic Associations of NZ president Fazim Arafeh told Mike Hosking they knew there was a risk.

"We used to think it's minimal, but obviously it's a bit more than what we thought."

He believes the 15-year-old can be rehabilitated.

"Certainly because he's very, very young in age, and obviously that was a main reason why he was persuaded to this destructive ideology."

The teen was sentenced to intensive supervision with a list of conditions, which if breached, could put him in prison.