The "hostile intelligence presence was all-pervasive" for New Zealand soldiers who served in Moscow, the NZDF now concedes.

New Zealand army veterans who served in Moscow late in the Cold War have won improved health benefits after a 16-year battle.

Kiwi servicemen were subject to "grotesque" attention from the KGB, the former Soviet spy agency, according to a document released by the NZ Defence Force and Veterans' Affairs under the Official Information Act.

Examples of the attacks were held back by Veterans' Affairs but former Kiwi soldier Ian Stobie was "chemically" interrogated by Soviet agents after being rushed to a Moscow hospital with appendicitis in February 1980. He was left unguarded by New Zealand embassy officials, contrary to good security practice, he told a Stuff reporter in 2013.

He awoke one day to find two Soviet men injecting him with a substance.

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"I was injected … I still have nightmares after being done over by the KGB in that Moscow hospital," he said.

He believes he disclosed the embassy lay-out and other secret details.

Former Kiwi soldier Ian Stobie was attacked by two KGB men in 1980.

The 11-page document contained more than three pages of blacked-out redactions but conceded for the first time that Kiwis serving at the Moscow embassy were subject to "break-ins, technical attacks (bugging), harassment, blackmail".

"Attacks by the KGB on New Zealand personnel and the premises in which they lived and worked are known to have taken place," the document stated.

The "hostile intelligence presence was all-pervasive". Veterans' Affairs now considers they faced a "moderate operational threat" in which casualties were likely.

It's believed more than 50 military engineers and police were involved. This count does not include diplomats and other New Zealand officials in Moscow between August 1, 1978, and July 31, 1992, the years covered by the change of status.

Stobie suffered post-traumatic stress disorder and other ailments and was denied improved health benefits when he first asked Veterans' Affairs for assistance in 2002.

He failed again when his health later deteriorated. He lives in Perth and is not eligible for full Australian health cover.

After more years of effort, the status of Scobie and other Moscow veterans was quietly improved by Veterans' Affairs earlier this year.

They get more healthcare support but not a better pension.

SUPPLIED New Zealand's Moscow embassy near the Kremlin is currently being renovated.

"Risks to our personnel are no longer … guns or bombs," said Veterans' Affairs minister Ron Mark when the change was announced earlier this year.

"If our people sustain injuries, or develop either physical or psychological illnesses because of their service, they deserve to receive our support," said Mark, who is also minister of defence.

Since 2015, Veterans' Affairs had reviewed about 20 historical postings and another 100 were scheduled for consideration.

BJ Clark had "no trouble" when he served in Moscow from 1979. He's now the national president of the Royal New Zealand Returned And Services Association (RSA) and last week recalled working day and night to finish improvements to the embassy.

There was a small bar inside the compound and the engineers in his unit rarely left. No soldiers were allowed to wear military uniforms for security reasons.

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