“Police and ambulance were called to a Shortland St property about 8.45pm last night, and on arrival found the woman in critical condition,” Farrant said.
“A scene guard has remained in place overnight, and inquiries are ongoing today to locate the person responsible, who left the scene in a vehicle.
“Members of the public can expect a police presence in the area to remain while these inquiries take place.”
Posts on social media from locals in the area have reported seeing armed police officers.
Hato Hone St John said they were notified of an incident on Shortland St at 8.44pm.
“One patient, in critical condition, was transported to Christchurch Hospital,” a spokesman said.
More to come.