UPDATED 9.39PM A 5-month-old baby has died near Waiuku today.

Police were called to a property this afternoon following the sudden and unexplained death of the baby.

The parents of the baby were speaking with police and assisting with inquiries.

The scene was tense.

Three police and security guards stood outside the home where the baby was found dead hours earlier.

A woman with a jack russell puppy tucked under her arm told media to leave the "very delicate" situation.

People sat in parked cars lining the street but offered no comment.

A member of the media was threatened when he went to take a photo by a male family member.

A local woman, who did not want to be named, passed by the house earlier in the day.

She saw the dead baby in a crib on the deck. A woman, who she thought must be the mother, was crying.

"It just looked like a baby sleeping.

"I was just shocked and sad. We're all just hearing about it now."

A male neighbour's wife saw the baby being taken from the car around 2.30pm today. He said the mother tried, unsuccessfully, to give it CPR. The family then started crying and shouting.

"She saw everything. It wasn't a nice look."

He said the baby was a little girl.

He said he heard the parents arrive home around 10pm last night.

Another neighbour said she knew as soon as she got home something was wrong.

She said she thought the family had five or six children.

"They're neat, beautiful kids."