Veteran British endurance cyclist Mike Hall has died after being struck by a car during the Indian Pacific Wheel race from Perth to Sydney, event officials said.
Organisers called off the remainder of the race several hours after the accident.
Police from the Australian Capital Territory said a male cyclist died at the scene following the collision on the Monaro Highway near Williamsdale. The cyclist was travelling north, just inside the ACT border with New South Wales state, when the crash happened.
More than six hours after the accident, race officials, after notifying his next of kin, confirmed in a statement that the cyclist was Hall, 35, from Harrogate, North Yorkshire. They called his death "a great loss to the global cycling community".
Hall was in second place in the race when his global positioning satellite (GPS) tracker stopped moving near the scene of where the collision was reported at 6.30am local time on Friday.
The 3,400-mile (5,500km) race began on March 18 in Fremantle, Western Australia, south of Perth. The leading rider, Belgium's Kristof Allegaert, had been scheduled to reach the finish line at the Sydney Opera House on Friday.
But he and other riders were taken from the race route following the decision to stop it.
"The Indian Pacific Wheel Race has been cancelled with immediate effect in light of this morning's tragic incident," race organisers said in a statement before confirming Hall's death.
"This is a difficult time for everyone involved, along with their families, and their well-being is our primary concern."
Police said the accident happened before sunrise.
"I can suggest, given the nature of the collision, an investigation into the circumstances would suggest the rider of the push bike died at the scene," said ACT Police Sergeant Chris Meagher.
"(The driver) will be spoken to later by our crash investigation reconstruction team. It's early in the morning, it's dark; there was no fog at the time."
The CyclingTips website said on Friday that Hall was regarded as one of the world's best ultra-endurance racers and held the record for the fastest completion of the Trans-Am and Tour Divide bike-packing races in the United States. He was the founder of the Transcontinental race in Europe.
About 70 riders from around the world started the Australian race, with Hall one of the favourites. The race was unsupported, meaning competitors did not have back-up or support teams travelling with them.
Race officials said a tribute ride was being planned for Hall in Sydney on Sunday.