A man has been arrested after two elderly people were attacked in their Napier home.
A man, 25, has been charged with wounding with intent to cause grievous bodily harm, police said. Other charges may follow.
He will appear in Hastings District Court tomorrow.
St John ambulance staff had turned up at the Napier house on Sunday thinking they were being called to a medical event, only to encounter the scene of an attack on elderly people at home.
Both victims remain in hospital in a stable condition today.
A 94-year-old woman and her son in his 70s were seriously injured in the attack at a Kennedy Rd unit about 7.46am on Sunday.
Another son of the 94-year-old told Stuff his mother, who lived alone, was doing well, but would struggle to live in the house where she was attacked again.
"She is doing remarkably well for the ordeal she has gone through. She's very stoic, and she's been unbelievable really," he said.
"The prognosis is that they will both recover fully physically, but obviously we have some concerns about the mental impact it will have on mum at that age."
The man told Stuff his brother had serious head injuries after the attack and would need to be monitored.
A St John spokesperson confirmed to Hawke's Bay Today that paramedics were alerted to the assault by a medical alarm activation about 7.46am.
"The call came via a St John Telecare representative after a St John Medical Alarm was triggered at the property."
"Three ambulances and one Rapid Response Unit responded to the scene."
They transported the pair to Hawke's Bay Hospital - one in a critical condition and the other in a moderate condition.
The spokesman said St John was providing support to its ambulance officers who responded to the incident.
Police tape still surrounded the unit on Monday while forensic investigators examined the scene beneath a tarpaulin by the front door.
Many doors to other homes in the varied neighbourhood were answered by barking dogs on Monday.
One resident in the area, who Hawke's Bay Today agreed not to name, said she had lived there for many years and only heard about the assault when police came to knock on her door.
She said the incident was certainly "out of the box" and "very scary".
Another resident said there were definitely vulnerable people in their community.
Age Concern New Zealand chief executive Stephanie Clare said the incident would make a lot of people feel on edge.
She encouraged people to reach out and have a conversation with their friends, family or their local Age Concern on freephone 0800 65 2 105.
"Our thoughts and best wishes go out to this family."