An Australian man has been found guilty of murdering his Canadian fiancée in 2011, by throwing her from the balcony of their 15th floor apartment in downtown Sydney.

Simon Gittany, 40, is convicted of murdering Lisa Harnum of Ontario in July 2011, following a bitter row that started after he learned the former ballerina was planning on leaving him.

Part of their argument was captured by a security camera in the building. In the footage, Gittany is seen at one point putting his hands over Harnum's mouth and appearing to drag her back into their apartment.

The judge-only trial has gripped Australian media for the past few weeks.

New South Wales Supreme Court Justice Lucy McCallum, who delivered the guilty verdict after deliberating for five hours, described the relationship as an abusive and controlling one.

McCallum said Gittany was in a state of “uncontrollable rage” when “he carried her to the balcony” and “unloaded her over the edge.”

Harnum plunged 15 storeys to her death.

Footage captured minutes later show Gittany frantically pacing inside the elevator.

In court, Gittany claimed Harnum suffered from bulimia and tried to commit suicide.

But the trial revealed compelling evidence against him. The balcony railing was clear of Harnum’s fingerprints, despite his claims that she climbed over it.

Court also heard that Gittany used electronic software to track her text messages and had installed pinhole cameras to spy on her.

Authorities found out about the cameras from a note written by Harnum and discovered in her pocket after her death. It read: “There are surveillance cameras inside and outside the house.”

"At some point it was a loving relationship but it turned into one which was about control and being dominated," Tim Stackpool, an Australian freelance reporter who has been following the case, told CTV's News Channel on Wednesday.

After the verdict, Gittany's girlfriend Rachelle Louise was heard screaming, "You're wrong.”

Meanwhile, outside the New South Wales Supreme Court, reporters gathered as Harnum's mother, Joan, reacted to the verdict.

"There's no winner in this case. Two families have had their lives dramatically changed forever," Joan told reporters.

She added she hoped her daughter’s legacy would become a “powerful wakeup call to young women and to parents, siblings and friends of these young women.”

Gittany will be sentenced on Feb. 5