Two detectives from Tasmania have been sent to New Zealand to interview a man named in a child sexual abuse inquiry as being a paedophile.

Australia's royal commission into Institutional Responses to Child Sexual Abuse named the man because it was thought he was dead.

But the 77-year-old is alive, living in Bulls with his partner and retired after teaching here without any alarm bells having been raised.

Tasmanian police yesterday announced a formal investigation into the allegations against him has been launched.

They've spoken to two former music students who made the allegations and who wish to pursue them.

The man has rejected both the allegations, and a claim by police that he fled the country to avoid arrest.