The man, aged in his early 50s, was airlifted to The Alfred hospital after the earth-moving truck he was driving tipped near the intersection of McSwains Road and Framlingham Road ust after 10am.

Relatives of the man said on Friday afternoon that he was in an induced coma with assisted ventilation.

Warrnambool Sergeant Martin Flannery said the driver was heading south along Framlingham when he failed to negotiate a bend and tipped the truck over on its right side.

"The scene has been examined and we are investigating the possible cause of the incident," Sergeant Flannery said.

"We're not ruling out that the vehicle may have been travelling at a speed not suitable for the bend."

Earlier, Thursday 4.30pm: A man in his 50s has been flown to Melbourne in a critical condition following a truck rollover in Framlingham.

He was flown to The Alfred Hospital on Thursday afternoon with upper body injuries after a single-vehicle rollover on the corner of McSwains Road and Framlingham Road.

Earlier, 12.30pm: A man is likely to be airlifted to Melbourne following a truck rollover in Framlingham on Thursday.

Emergency services were called to the corner of McSwains Road and Framlingham Road, Framlingham around 10.20am this morning to reports of a single-vehicle rollover.

An Ambulance Victoria spokeswoman said at 12.30pm that that an ambulance helicopter had been dispatched to the incident and he was currently being assessed at the scene for upper body injuries.

Three CFA crews were on scene along with SES and Victoria Police.

Terang SES controller Jamie Rowe said teams with the assistance of Warrnambool CFA had to execute a rapid extrication to free the trapped driver.

The investigation has been handed to Victoria Police.

McSwains Road is closed near Framlingham Road. Drivers should consider using Framlingham Road and the Hopkins Highway instead.

More to come.

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