A cyclist is fighting for his life after being found unconscious in the middle of a Gold Coast street in an alleged hit-and-run.

The 68-year-old man was cycling on the corner of Dungogie Dr and Tallebudgera Connection Road, Tallebudgera, when he was allegedly hit by the car at about 6am on Monday.

Bystanders called emergency services after finding the man unconscious in the middle of the road.

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Paramedics rushed to the scene, where they treated the man for life-threatening internal and head injuries.

He was taken to the Gold Coast University hospital in a critical condition.

“It will be alleged that the cyclist was hit by a vehicle, which did not remain at the scene,” police said.

“An 18-year-old man voluntarily attended the Palm Beach Police Station around 8am and was subsequently arrested.”

A white Toyota dual cab ute was seized by police at Worongary.

All roads near the crash site are now reopened.

The Forensic Crash Unit is investigating the incident, and anyone with information or dashcam footage is asked to contact police.