Pike River families spokesman Bernie Monk was "shocked" to hear the names of a number of victims of recent New Zealand disasters had been used in online fraud.
Monk said authorities had alerted him to the fact someone had stolen the identities of a number of victims, including those from the Pike River Mine explosion on November 19, 2010.
"It took me by surprise, but I was appreciative the police were on to it," he said.
Detective Senior Sergeant Iain Chapman of the Auckland City District Financial Crime Unit said the conman got the personal details of 29 identities in February 2012 from the A Memory Tree website.
The website is the country's largest death information website, which allows people to set up remembrance pages for those who have died.