Four people have died, including two young children, and two others have been left fighting for life in a horror head-on crash that has shut a highway in Queensland.

Emergency services were called to the Capricornia Hwy, between Comet and Blackwater in the state’s Central Highlands, after two cars collided just before 11am on Sunday.

Paramedics rushed to the scene, however, four people were declared dead upon their arrival.

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Police said initial investigations indicated a Holden Commodore travelling towards Blackwater struck a Toyota Hilux ute travelling in the opposite direction.

The Holden driver, a 28-year-old man, and his three passengers, a 6-year-old boy, 7-year-old girl and 32-year-old man, all died in the crash.

Two men inside the ute sustained serious chest and abdominal injuries.

One 28-year-old man was taken to hospital in a serious but stable condition, and a 27-year-old man was flown to Brisbane for treatment to life-threatening injuries.

“The Capricorn Highway remains closed in both directions and is expected to remain closed into the evening,” police said

“Due to the complexity of the incident, there is no further information available at this time.”

Investigations are ongoing.