Seven people were taken to Hawke's Bay Hospital after a miniature train came off the rail in Havelock North on Saturday.
Among them was a three-year-old; the others are all adults. The child and five adults have been discharged but one will remain in hospital overnight and is in a stable condition.
The Ambulance Service says it was called to the Keirunga Park Railway just after midday after the train's three carriages, which were carrying 23 people, tipped over.
The Department of Labour is investigating.