A teenager is fighting for life after a devastating multi-vehicle crash on the Bass Highway at Westbury in the state's north last night.
The 17-year-old from Gagebrook was thrown from a blue 2002 Holden Commodore ute which police believe was travelling on the wrong side of the road.
It had struck a Toyota Landcruiser carrying a family of six - including four children under the age of 12 - from Caveside, an empty fuel tanker and then went head-on into Mazda CX-5 driven by a 35-year-old mother and her 12-year-old son from Deloraine at about 8 o'clock.
Initial investigations suggest the male passenger wasn't wearing a seatbelt at the time.
He was taken to the Launceston General Hospital and then airlifted to the Royal Hobart Hospital in a critical condition, while 5 others received non-life threatening injuries.
The driver of the ute was conveyed to the Launceston General Hospital with less serious injuries along with the driver of the Mazda who was suffering abdominal pain. All children escaped injury along with the truck driver.
The Bass Highway was closed for about six hours last night while emergency services attended the scene.
Police will return to the scene at 3pm today to continue investigations - the road will be closed for about 30 minutes.