Senior Sergeant Roy Appley said reports of powerline tampering and copper and electrical supply thefts have increased over the past 10 days.
"Incidents are occurring across Christchurch, including multiple central locations such as Disraeli St in Addington, the area surrounding Hillview Rd and Phillips Rd in Phillipstown and Brougham St, they are as wide spanning as West Melton, Halswell, and Marshlands.
"Police have informed community patrol and frontline police units on what to look out for and have communicated with businesses and residents in affected areas."
Officers are also talking to scrap metal dealers as part of the investigation, Appley said.
"On multiple recent occasions powerline tampering and the theft of copper from the powerlines have led to power outages on affected streets.
"Typically once the offenders get what they want, the powerlines are left in an exposed and dangerous state.
"In one occasion powerlines were tampered with and left broken outside of a Phillip St pre-school.
"Fortunately, no one has been harmed, but as far as police are concerned it is only a matter of time."
In February, three men were charged over powerline tampering and electrical thefts in the Bromley area.
“Our message to offenders is to stop this behaviour before someone, including yourself, gets hurt.
“You are putting yourselves and others at extreme risk of electrocution, for such a small return.
"We are appealing to the public for any information that could assist in identifying and locating those involved.
“If you hear anything out of the ordinary overnight, do not think nothing of it.
“We need Christchurch residents to be aware of the risk of exposed or damaged wires – do not touch them and call Orion on 0800 363 9898 straight away,” said Appley.
Residents should call 111 if they see anyone acting suspiciously around power poles and lines or phone 105 after the fact.
