According to the Australian Broadcasting Corporation, the police told parliament's intelligence and security committee that it obtained warrants to access the metadata of two journalists, who were not identified, on 58 occasions during that period, Efe news reported.
The authorities used a 2015 amendment to espionage legislation that forces telecommunications companies to keep phone and Internet records, as well as other metadata, of users for up to two years.
The revelations of spying on journalists comes during a time of tension between the media and the Australian authorities.
In June, police conducted an eight-hour search at the ABC headquarters following a series of articles, dubbed the Afghanistan Files, and the leaking of classified documents in 2017 on alleged unlawful killings by Australian special forces in Afghanistan.
The police also searched the home, computer and mobile phone of News Corp journalist Annika Smethurst in Canberra because of her information about the Australian government's plans to extend more powers to intelligence agencies to spy on its citizens.
The country's mainstream media has criticized these raids as an attack on press freedom and demanded an end to them.
Since 2014, Australia has enacted a series of laws criminalizing the disclosure of information linked to state interests, establishing new forms of espionage and allowing access to the metadata of citizens, among others.
( With inputs from IANS )