Police have given Christchurch's hacked crypto currency exchange the all clear to reopen whenever they like

But the company's website remains offline and its founders aren't responding to queries about when, or if, the company will resume trading.

Cryptopia's social media accounts all remain dormant.

Police aren't revealing how much crypto currency was taken during last month's online heist.

Some experts are suggesting it's as much as 23-million dollars.

However Detective Inspector Greg Murton says investigators have finished the main part of their work and Cryptopia management have full access to their business premises.