Police are investigating the circumstances surrounding the double fatality at the Church Parade intersection just to the north of the town Kingston, near Creswick.

The collision, which involved a Kenworth truck and a Toyota Rav4, took place just after midday. Police said the truck had failed to stop at a give way sign at the intersection.

A five-year-old boy and 37-year-old woman travelling in the Rav4 died at the scene. A dog also died.

The male driver of the 4WD has been taken by road ambulance to hospital with minor injuries and was treated for shock. He remains in a stable condition.

Another passenger, a nine-year old boy, has been rushed by air ambulance to Melbourne.

An Ambulance Victoria spokesperson said the child had suffered facial injuries and was now in a stable condition.

All the occupants of the car were reportedly from the same family, who live in a suburb of Bendigo.

The driver of the truck, a 59 year-old West Australian, is believed to have been travelling west along Church Parade. He was uninjured and is currently assisting police with their enquiries.

The Rav4 flipped over and came to rest on the south side of the main Kingston Road thoroughfare where emergency workers cordoned it off.

The Victorian road toll at this stage for 2019 is 263 compared to 211 in 2018.

Detective Sergeant Paul Lineham, who is heading the Major Collision Investigation Unit dealing with the crash scene, said the collision had caused "needless" loss of life. He urged drivers to take extra care for the remainder of the holiday period.

The road will remain closed until after 9pm while police carry out further investigations.

EARLIER

Emergency services were first notified at 12.19 on Sunday afternoon to reports of a car rollover at the location about 26 kilometres north of Ballarat.

An ambulance spokesperson said an air ambulance was on the scene and would be transporting a little boy for further treatment in Melbourne. The air ambulance has since left the scene.

A man in his thirties is being taken to Ballarat Base Hospital, and a number of people are still being treated at the scene.

Two people are believed to be still trapped in one of the vehicles.

The extent of the injuries of those involved are not yet known.

A police spokesperson said that major collision investigation detectives were heading to the scene.

The road is currently closed in both directions.

More to come.

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