Cyberattacks forced New Zealand's stock exchange to halt trading for a fourth straight day Friday, with the country's spy agency called in to help combat the ongoing security breaches.
"We are currently experiencing connectivity issues which appear similar to those caused by severe DDoS attacks from offshore this week," NZX said in a statement.
Distributed denial of service (DDoS) attacks involve disrupting computer networks by flooding them with traffic.
There have been similar temporary training halts daily since Tuesday.
The shutdown on Friday came despite the NZX putting additional measures in place to maintain connectivity before the market's opening bell.
"NZX has been continuing to work with its network service provider, Spark, and national and international cybersecurity partners, including GCSB, to address the recent cyberattacks," it said.
The GCSB is New Zealand's intelligence agency, tasked with safeguarding the country's infrastructure from online attacks.
The disruption has hit in the midst of earnings season, normally one of NZX's busiest periods, when companies such as Air New Zealand and telecoms carrier Spark announce their annual results.
NZX has remained tight-lipped about who is behind the attacks.
Experts have told local media possibilities include a state-sponsored incursion, online activists with an anti-capitalist agenda such as Anonymous, or a criminal enterprise seeking a ransom.
Regulators from the Financial Markets Authority (FMA) were in close contact with NZX.
"The NZX has informed us that no internal systems have been compromised and trading information has not been breached," the agency said.
"In the circumstances, the FMA supports the decisions of NZX to halt trading, for periods where issuers are unable to release information to the market and investors do not have access to disclosures on nzx.com."