Two people are dead and a child critically injured in a serious incident in South Auckland this morning.

A police cordon surrounds a property on Sunnyside Cres in Papatoetoe.

Police confirmed two bodies - that of a woman and a man - had been discovered today after officers arrived at the home at 9.50am.

"Police attended the address and located the body of a woman inside a bedroom.

"A child was also located in the room with critical injuries and he has been transported to Starship Hospital," a statement said.

"A further search of the address revealed the body of a man who was located deceased inside the property's garage."

A St John spokeswoman confirmed they received a call from Police at 10.08am.

Two intensive care paramedics were among the St John team sent to the scene and one person was taken to Starship Children's Hospital in a critical condition, she said.

At the scene early this afternoon, a number of police officers stand guard while others are dressed in white jumpsuits carrying out a scene examination.

The circumstances of the deaths and exactly how the two people died and how the child - a boy - was injured are not yet known.

Police would only call the incident a "tragic event."

"Police are working to establish the circumstances and piece together what has occurred."

Officers will remain at the scene today as a scene examination is carried out and police continue to speak to "a number of individuals" in relation to the incident.

Detective Inspector Colin Higson said authorities are not looking for anyone at this stage and believe the man and woman are known to each other. Their relationship to the child has yet to be explained.

Police are now working to confirm identities and contact next of kin.