Some earthquake-damaged buildings can't come down quick enough as "foolish" graffiti artists are pushing the limits to spray their tags.
Vandals have scaled some of the city's biggest landmarks, including the dilapidated AMI Stadium, the old brick railway station on Moorhouse Ave, and the Canterbury Brewery building, to leave their mark.
They've scaled security fences and demolition machinery, beaten security measures and denied gravity to spray their distinctive signatures.
But police are concerned that the practice will end in tragedy and have urged them to stay away.
"They're putting themselves at risk, and more importantly, others who have to extract them if things go horribly wrong," said central tactical co-ordinator Senior Sergeant Glenn Nalder.
Graffiti vandalism costs city ratepayers more than $1m every year and the city council has teamed up with police to try and stamp it out.
But now the local graffiti artist population have turned their attention from shop fronts and residential fences, to the quake-hit structures destined to be demolished.
Police say it's still an offence to vandalise a building which may not be round for much longer, saying it's still someone's property.
"It's just something else that this city doesn't need," Mr Nalder said.
"These sites are being worked on, and demolished for a reason - they are unsafe.
"It's foolish and it needs to stop before it gets out of hand and someone has a fall."
Graffiti is an offence punishable by up to three months in prison and a $2000 fine.