Christchurch Police say they are confident recent arsons across the city are not linked - and are calling on residents to be on the lookout for suspicious activity around vacant properties.
Detective Inspector Greg Murton says investigations into recent suspicious fires show they are likely to have been the work of different individuals - and are mostly "opportunist" incidents.
Police also say that overall levels of reported arson across the city are no higher than normal.
"We are seeing suspicious fires occurring right across the city - not just in the residential red zone," he says.
"However, vacant homes are always a potential target for arsonists, so we are alert to the risks around red zone properties.
"Out of around 60 suspicious fires across the greater Christchurch area in the past three months, the vast majority have been things like wheelie-bin fires and vegetation fires. House fires are a small proportion overall.
"And of all the reported incidents, fewer than one-third were in residential red zone areas.
"Overall, the rate of suspicious fires at present is no higher than historical averages."
Detective Inspector Murton says the incidents do not follow a single pattern. "Some fires are set inside the vacant house, others are set outside. In some cases offenders have used vegetation or dried leaves, while others make use of rubbish left lying around.
"The majority of incidents appear to be opportunist fires. We're confident we are not dealing with a firebug or serial arsonist."
Detective Inspector Murton says Police are working closely with CERA and the Fire Service to identify risk areas where properties are being vacated, and to take preventive measures.
"We are stepping up our preventive work as the number of vacant houses increases, including increasing our patrols through areas where homes have been vacated.
"These will also include foot patrols and will particularly focus on the overnight period when the majority of these incidents occur.
"We're also working with groups such as Community Watch who can help be the 'eyes and ears' in local neighbourhoods.
"But we are also urging residents and members of the public to help, by keeping an eye on their own neighbourhoods.
"Most importantly we urge anyone who sees suspicious activity around vacant properties to contact police urgently.
"The message is - don't wait. If you see suspicious activity call 111 immediately and we will respond and investigate."
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