The second such breach to occur in Australia in the past two weeks has resulted in hackers target specific one of the country's largest pathology providers and stealing the medical data of thousands of patients, according to Reuters. This attack has increased concerns about how businesses collect and secure sensitive customer information.

The Thursday discovery added to the flood of hackings that has rocked the largest businesses in the nation, and Australian Clinical Labs Ltd. shares plummeted to their lowest level since going public last year. Hackers had obtained the personal information of all four million of Medibank Private Ltd's customers, according to a notification made a day earlier by Australia's largest health insurer.

 The government cybersecurity agency informed ACL in June that its data had been posted on the dark web, a network of websites only accessible through specific browsers. ACL stated on Thursday that it first learned of the unauthorised access to the IT system of its pathology unit, Medlab, in February and was told that no information had been compromised.

According to the Reuters report, ACL then employed forensic experts to examine the 'complex and unstructured' data-set discovered there and discovered that 223,000 patients' data, including the medical and health records of roughly 18,000 persons, had been exposed in the hack.

Melinda McGrath, chief executive officer of ACL, stated in a statement, 'There was no ransom demand or proof of data misuse, but we realise the worry and inconvenience this incident may cause to those who have utilised Medlab's services and have made steps to identify anyone affected.

Since Sept. 22, when the country's second-largest telecom, Optus, which is owned by Singapore Telecommunications Ltd., reported a security breach and theft of personal data from roughly 10 million user accounts, or 40% of the country's population, businesses in Australia have been preparing.

The grocery company Woolworths Group Ltd recently disclosed that millions of users of its website for bargain shopping had had their personal information hacked. A number of smaller, unlisted companies also disclosed data breaches caused by hackers, which led lawyers to question how much data private organisations should gather and how long they should keep it.