The location of defence force planes, criticism of the foreign affairs ministry, and details about a New Zealander arrested on drugs charges in South America were obtained when a Cabinet minister's email account was allegedly hacked.
Fairfax Media last week revealed that Foreign Affairs Minister Murray McCully's private Xtra account had been hacked last year.
Concerns were heightened because McCully had asked staff to send diplomatic information and other potentially sensitive information to the address.
A group calling itself "The Comrades" has now contacted Fairfax Media with alleged copies of the emails obtained.
The group's leader, who claims to be a Russian called Yuri Petrov, said it was easy to hack into the account, although the New Zealand Government was not important to them.
"The main (reason) being for military intelligence. To gain more information. If it is good information, we sell it. If bad/personal, we keep."
That intelligence included the likely position of defence force planes often used by McCully when visiting the Pacific and Asia.
A series of emails from staff in his office suggest dates for trips in May and June of last year.
"Most of July is looking very difficult for the NZDF - no 757s available, and only one C130."
Other emails, from an unidentified insider, point to McCully's concern about the state of the Ministry of Foreign Affairs and Trade (MFAT).
The insider tells of the "mindless, wasteful admin crap" he saw in the Wellington office.
"JA (John Allen) does not have the system humming as I expect he would have had."
Staff at MFAT are expected to be told tomorrow of plans to cut up to 300 jobs and force many to reapply for their positions.
Messages from April last year, show how MFAT officials dealt with the arrest of Sharon Armstrong on drug charges in Argentina.
The decision was made to "keep this at an operational level" and for McCully not to comment to media.
"Armstrong has advised the Embassy staff that she does not wish her name to appear in the media in NZ and would appreciate every effort to ensure her name and circumstances are kept confidential."
Armstrong was later interviewed at length by New Zealand media from the Buenos Aires prison where she was detained.
The need for Pacific nations to "resist China" was also discussed in an email which said the region was getting "precious little outcome" for the millions of dollars being spent on meetings.
"Some outfit we are supporting under NZ aid flew a person to Noumea to give a 12 minute presentation," an advisor wrote to McCully.
In his last email contact, Petrov said he would not talk to, or be interviewed by, New Zealand media anymore.
"We are done and now we move back to our other targets."
Fairfax Media has not been able to confirm the identity of the alleged hackers, it was originally thought international hacking group Anonymous was behind the infiltration.
McCully last week confirmed his account had been hacked but said it largely contained media reports.
He said he was not able to confirm the authenticity of the allegedly hacked emails.
"In any case we would not comment on stolen material."
In 2000, a Miami teenager known as "c0mrade" online was sentenced to six months in prison after he hacked into a United States military computer network and illegally accessed 13 Nasa computers.
- Fairfax Media
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