Police have charged 38-year-old Rajwinder Singh with murder over the death of Far North Queensland woman Toyah Cordingley in October 2018.
Her body was discovered by her father after she failed to return home from walking her dog on Wangetti Beach.
Mr Singh, who arrived in Cairns this afternoon after being extradited from India via Melbourne, is expected appear before the Cairns Magistrates Court on Friday on one count of murder.
Detective Inspector Sonia Smith on Thursday afternoon said about 100 police worked on the case in the first few months, and the Australian Federal Police's work in New Delhi had been critical.
"Right up until we took custody of the prisoner at the aircraft, they were working tirelessly and relentlessly for us."
"We are very relieved to be at this point, and we will now start the judicial process."
Parents react
Detective Inspector Smith read statements from Ms Cordingley's parents.
"I am so relieved to have this person back here in Queensland," the statement from Ms Cordingley's mother Vanessa said.
"We thank the community for the ongoing love and support throughout these difficult times."
Ms Cordingley's father Troy said Mr Singh's arrival in Cairns was one more step in the process that he can "cross off my list".
"I will continue to stay as strong as I can."
Mr Singh touched down in Cairns just before 1pm from Victoria, where he appeared briefly in the Melbourne Magistrates Court on Wednesday for an extradition hearing.
Prosecutors told the court police have DNA evidence linking Mr Singh to Ms Cordingley's murder.
He had been working as a nurse in Innisfail at the time of Ms Cordingley's death and was living with his wife and three children.
He flew out to India the day after Ms Cordingley's body was found.
Detective Inspector Smith, who has been working on the case since the beginning and flew to India to bring him back to Australia, said it had been a long journey.
"Our primary focus has always been ensuring justice for Toyah, her family and friends without compromising the investigation," Detective Inspector Sonia Smith said.
"We have been determined to find answers for Toyah's family and the work of all involved has been meticulous since that terrible day."
Cairns state MP Michael Healy said it was important that the community now let the justice system run its course.
"It's been a long four years ," Mr Healy said.
"There is a legal process that we need to go through, so we don't need to be seeing people making outrageous comments.
"This is about justice for Toyah and we don't want to see anything jeopardise that."
A case that shocked a community
Ms Cordingley worked at a local pharmacy and volunteered at an animal shelter at Port Douglas.
Police said she had done some shopping at Rusty's Markets before picking up her dog, Indie, and drove to Wangetti Beach, a 40-minute drive north of Cairns, on October 21, 2018.
When she failed to return home, her family went to the beach with torches to search for her.
They found Indie tied to a tree, but no sign of Toyah.
The next day, police and SES crews began combing the beach, but it was her father who discovered the body, close to where Indie had been tied up.
Four-year police investigation
The crime sparked a protracted police investigation, with police leaving no stone unturned.
Local residents were asked to provide DNA samples as police reviewed hundreds of hours of dashcam vision supplied by the public.
Tourists who had visited the lookout that looms above Wangetti Beach were also asked to look through their holiday snaps.
In November last year, four years after her body was found, the Queensland government offered a $1 million reward for information.
Detective Inspector Smith would not say whether the reward had been paid out, saying it was a confidential process.
Rajwinder Singh was arrested while visiting a doctor in New Dehli and placed in Tihar prison in New Dehli, where he shared a cell with 90 other inmates.
He waived his right to challenge an extradition order to bring him back to Australia and told the courts he wanted to fight these charges, expediting a matter that could have stalled in the Indian courts for years.
Mr Singh has maintained his innocence and has told several media outlets in India that he did not murder Ms Cordingley.
