A government ministry was the victim of more than 180 million hacking attempts in less than 18 months.
Three government departments confirmed they have been targeted by hackers and many more have revealed they are under "constant" cyber-attacks.
Foreign hackers are responsible for many of the incursions and government departments are investing in complex IT defence systems to fight a bombardment of digital threats and malicious malware.
In the wake of last month's Budget "hacking" scandal, the Weekend Herald lodged numerous Official Information Act requests to government departments.
The responses reveal a disturbing pattern of repeat attacks and multiple instances