Speaking on the arrest, Detective Chief Inspector Chris Olen said: "A 70-year-old man has been arrested this morning shortly before 8 o'clock in relation to the murder of Lyn Dawson".
The 36-year-old mystery concerns the disappearance of Lyn Dawson from her home on the Northern Beaches of Sydney in January 1982.
An inquest in 2003 found that Chris Dawson, a former high school teacher, had started an affair with a 16-year-old student who moved in with him within days of his wife's disappearance.
Fuller acknowledged that media reports had contributed to police obtaining additional statements relating to the case.
Fuller said authorities have not located Dawson's body, and that finding her remains is "not crucial to finalising the matter", but maintained "we certainly won't give up on that search".
A spokesman for Chris Dawson's family said they are "disappointed" in yesterday's explosive developments, and claimed there was "clear and uncontested" evidence Lyn was alive long after she disappeared.
An application for bail was refused by Queensland magistrate Dennis Kinsella and Dawson was taken into custody of NSW detectives.
"A team of dedicated detectives has been investigating this case over the past three years", Det.
Chris Dawson 70 has been arrested and is expected to be charged with his wife's murder
Dawson's family said in a statement they had no doubt he'd be found innocent.
He is expected to be charged with Lynette Dawson's murder.
Mr Dawson will face a NSW court later this week.
"We have sold homicide before without identifying the body", he continued.
However, prosecutors have previously said there was insufficient evidence to lay charges.
Homicide Squad Commander, Detective Superintendent Scott Cook, also praised the work of Strike Force Scriven investigators who have worked tirelessly to uncover the truth behind the cold case.
In September investigators spent nearly a week digging up the Dawsons' former Bayview home but found no human remains and no significant clues.
Since Lynette's disappearance, Dawson claimed she had run away to life with a religious cult in a remote area of NSW.
He said two witness statements in particular helped piece the evidence together.
"We've had a cry, we've cuddled, we're just completely over the moon that something has finally happened", he told The Australian.