The hunt is on for those behind the New Zealand Stock Exchange (NZX) cyberattacks after it was repeatedly targeted by distributed denial of service attacks last week.
On Friday, the Government Communications Security Bureau (GCSB) was directed to help the NZX with the attacks amid reports a crime syndicate was demanding Bitcoin payments.
The NZX website had been targeted by repeated attacks since Tuesday.
Rush Digital founder Danu Abeysuriya told The AM Show the attackers can be difficult to track.
"Whoever's doing it has a lot of resources organised so it could be a really cashed-up criminal gang, which is highly likely, or something more," he said.
"It's highly likely that it's a ransom-type attack."
He said technology company Garmin recently paid a ransom of about 10 million Euros following a cyber-attack.
"I really hope NZX doesn't pay any ransom and just keep fighting the good fight," Abeysuriya said.
"The Government has a lot more resources - the GCSB's involved right now so when you've got a lot of resources on the other side in the good fight, if you leave the slightest bit of evidence it means there's a good chance it'll be uncovered."
He said the NZX cyber-attacks were "real economic crime".
"Whoever gets apprehend for this - throw the book at them," he said. "You'd have to be a complete idiot to be involved with this because it's going to hurt if you get caught."
Finance Minister Grant Robertson said on Friday he wasn't aware of any ransom demands.
Auckland University of Technology's department of computer science professor Dave Parry said the attacks appear to be at a rare level of sophistication.
"Unfortunately, the skills and software to do this are widely available and the disruption of COVID and people working from home all over the world potentially with lower security on their computers means that these attacks are easier than usual," he said last week.