Queenstown police are appealing for witnesses to a massive house fire which destroyed the upper story of a house in Glasgow St early yesterday morning.

Detective Sergeant Brian Cameron of Queenstown police said a joint fire service and police investigation into the cause of the blaze was launched yesterday.

‘‘As the property appears to have been unoccupied for some time, the fire was being viewed as potentially suspicious,’’ he said.

Emergency services were called to the fire at 5.50am after neighbours were woken by loud noises coming from the property.

Queenstown and Frankton volunteer fire brigades arrived within minutes to fight the fire which was fully engaged, Mr Cameron said.

Police were yet to speak to the overseas-based owner of the property who lived in a remote location but had managed to contact a family member of the owner, he said.

Scene examiners from the fire service and police spent Saturday morning investigating the fire while officers went door-to-door seeking witnesses.

Anyone who had seen or heard anything prior to emergency services being alerted at 5.50am should contact Queenstown Police.

- © Fairfax NZ News