Internet service provider Paradise has brought in a forensic investigator to hunt down hackers who gained access to its system this month.
The TelstraClear-owned provider said email and web services were disrupted but the attack posed no threat to customers.
A TelstraClear spokesman said one of three servers was taken offline on January 20 after routine checks discovered someone had hacked into the system.
"We don't know exactly what they were going to do because we stopped them before they could do it.
"They weren't up to any good obviously."
The internet provider said a specialist investigator was tracking down the hackers and action could be taken against them.
"We'll know in the fullness of time but the people who do this are good at hiding their identity and location."
The server was back online the next evening to start clearing a backlog of emails. Customers with websites had service restored by Saturday.
The server was taken offline before access or corruption of customer information was possible.
The server shutdown and resulting email backlog prevented the internet provider from telling customers.
"Any ISP anywhere around the world is under constant attack from people trying to do malicious things," the spokesman said.
Paradise is advising customers with websites to change their passwords as a precaution.
The service
* Paradise is a TelstraClear-owned internet service provider.
* It has about 110,000 customers.
* It is ranked in the top three internet providers.
Paradise tracking hackers
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