Timaru police are speaking to a man in his 20s in relation to the alleged abduction of a boy last week.
The nine-year-old was found distressed and injured near a bridge about 15km from Oceanview Heights School last Thursday.
Inspector Dave Gaskin says the man is known to the boy but not related to him.
He says public information led to officers tracking down the man.
He cannot say whether the man will face charges yet.
School checks safety procedures
Oceanview Heights School principal Jenny Langley says the incident has shocked the school community and forced it to recheck its safety procedures.
Ms Langley says staff have met to make sure their safety procedures are up to standard, and she's happy with the result.
She says there has been significant community support for the boy, who remains in hospital in a stable condition with superficial facial injuries.
"A number of our parents and community members have provided little activities and things, to be taken up to the hospital, and cards, and all sorts of good wishes for him, so that's been the predominant reaction from our tight-knit community."
Inspector Gaskin says police spoke to the boy on Tuesday afternoon, for the second time in as many days.