Eighteen police and related staff are involved in inquiries after a 37-year-old woman was found unconscious in her rural Alexandra home on Saturday.
The woman was in the intensive care unit at Dunedin Hospital last night in a "serious but stable" condition.
The woman, whose name has not been released, was flown by helicopter to Dunedin Hospital with serious head injuries after police and ambulance were called to the house about 9.40am on Saturday.
Detective Senior Sergeant Colin Blackie said she was undergoing scans and other medical assessments yesterday.
He said a man apprehended in relation to the incident was being assessed at the mental health unit of Wakari Hospital in Dunedin.
"Pending the assessments, a decision will be made by police on what or any charges he will face," Det Snr Sgt Blackie said.
"It was too early to say what prompted the incident and the interviews of the persons allegedly involved, witnesses, psychiatric assessments and scene examination will take a number of days, by which time a clearer picture will become apparent."
At that stage, a decision would be made on possible charges.
Det Snr Sgt Blackie said the man was known to the woman, and police were not looking for anyone else in relation to the incident.
Police found the man, whose name has also not been released, a short distance from the address where the woman was discovered on Saturday.
The man was on foot and was taken into police custody before being transported to Dunedin.
Two children were found at the house by police on Saturday and Det Snr Sgt Blackie would not say whether they had any relationship to either the woman or man.
A forensic examination of the house was expected to be completed last night or this morning.
Det Snr Sgt Blackie said staff from the Environmental Scientific and Research Institute at Christchurch were helping police in the investigation.
In total, about 18 people were involved, he said.
