The Conservative Party says dirty politics have become dangerous politics after a candidate's car hoardings were set alight.
New Lynn representative Steve Taylor says his neighbours alerted him to the fact that the political signs - which were affixed to a trailer - were ablaze.
Fire fighters put out the blaze.
The car had been parked at Taylor's home, where he lives with his wife and two young children.
Flames could easily have reached the house, Taylor said.
"This is a wilful act of destruction and very risky to my family as we live in a fairly bushy area. It could easily have reached the house while we were sleeping."
Thanks to the two nearby fire stations and a quick-thinking neighbour, this wasn't the case, he said.
Taylor said he believed the motive was political.
"We're less than one month from the election - I've got some good support out here and this level of political attention seems to be escalating."
Conservative leader Colin Craig said the incident was a reflection of a wider criminal problem.
"This election it's very clear to us there's far more damaged hoarding and defacing than ever before.
"Someone prepared to set a trailer on fire might be prepared to set a house on fire."
When asked what he would say to the culprits if they were caught, Craig said: "They're probably not going to vote for us if they are setting our signs on fire, but maybe they'd like to own up now and not wait until we're in Parliament after September 20."
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