Police are investigating the incidents, which the Otago Daily Times believes to have affected up to 40 businesses.
Constable Peter Reed said Wanaka police put out a fire in the utility box on the corner of Brownston St and Dungarvon St at about midnight. Another box on the Brownston St and Helwick St corner was also found to be damaged this morning.
It appeared that the locks have been picked and somebody had set a fire inside the boxes using kindling in both cases, Const Reed said. Police are appealing for witnesses in what may have been a prank or intentional damage.
ODT Wanaka bureau chief reporter Marjorie Cook said some of those spoken to, who were left without phone and internet, have had some form of intermittent services restored but have described the fault as "inconvenient and potentially costing them quite a lot of money."
It is believed that work to restore the damaged telecommunications boxes could take until later this afternoon.
Wanaka New World health and safety officer Adrienne Taylor said the fault had not compromised the supermarket's trading ability today.
