John Howard's and Tony Abbott's busts along the Prime Ministers Avenue in the Ballarat Botanical Garden have been damaged and sprayed with vile messages.

Mr Howard's has been defaced with red paint and sprayed with the word "homophobe".

Vandalism on Tony Abbott's bust labelled him a "pig" and facist".

Mr Abbott was honoured only last week in the Queen's birthday Honours list for his services to Australian politics.

The vandalism comes at time when historical statues throughout the world are being questioned, as anti-racism movements sweep the globe, however the wording in Ballarat's attack seems to lack any of this specifically racially based anger.

But the latest assault on the public art did have a particular political flavour, targeting the two most recent Liberal party Prime Ministers on display. However it has not been the first defacing of either the avenue or some of the garden's other statues.

The most frequent attacks in the gardens can largely be attributed to a mindless destruction of public art. This has extended to the valuable dozen Stoddart marble statues, donated in 1884 and one of the gardens greatest assets, which have come under repeated attack.

In 1993 Spring and Hercules statues are pushed from their pedestals by vandals, causing them to smash. In April 2002: Vandals smashed Hebe, Leda and Flora Farnese.

In May, 2006 the Botanical Gardens had to be locked every night, due to theft and vandalism over a 12 month period.

In 2011, less than 12 months after the Stoddart marble statues were fully restored to their positions, they were vandalised again, with three of them being graffitied.

Police and City of Ballarat staff are investigating the latest damage and council staff have undergone cleaning works.

A police media spokesperson said the crime took place between midnight and 2.15am last night. They said police were looking for witnesses.

The Courier spoke to the chair of the Friends of Ballarat Botanical Gardens foundation Elizabeth Gilfillan who said:

"I'm devastated about the statues," she said.

"We value each each prime minister in that avenue. To single any out is a shame.

"These are sad times. This has been very divisive. Art is something that should unite us rather than divide us."

Ms Gilfillan said she was not sure additional security measures would work - and that they would be a massive step to take.

The Ballarat mayor Cr Ben Taylor said: "It's vandalism, it's pretty disappointing that people are willing to go that level."

"It doesn't matter what statue it is, it's vandalism first and foremost. It shouldn't be acceptable in our community."

The new interim CEO of the City of Ballarat Janet Dore echoed Cr Taylor's words, saying: "Our city does not condone any form of graffiti or vandalism on its public assets, regardless of people's beliefs or rising public sentiment, and I am certain our residents will be equally as disgusted by these actions."

The federal member for Ballarat Catherine King said she was "disappointed to see the vandalism of the two busts overnight."

"Our city is known nationwide for its history, and the Prime Ministers' Avenue is an important part of that.

"Whether you agreed with the policies of those Prime Ministers or not, they have played an important part in our nation's history and are deserving of respect.

"The Prime Ministers' Avenue is valued because it honours all of our Prime Ministers, no matter which party they stood for."

The iconic Prime Ministers Avenue showcases a collection of 28 bronze busts dating from federation.

They cost about $30,000 each. All Prime Ministers feature, except for Malcolm Turnbull and Scott Morrison.

Malcolm Turnbull is expected to be unveiled shortly.

It is not the first time the busts have been defaced, although perhaps the most damaging.

In 2017, Mr Abbott's bust was draped in a crown of onions, an obvious reference to the time he ate a raw onion on television.

It was also plastered with stickers, which were easily removed.

The mayor at the time, Samantha McIntosh, said respect should be shown to all Australia's former leaders.

"Without any doubt, there should be absolute respect for the position of prime minister," she said in 2017.

"Any of the prime ministers from over the years of Australia history have worked exceptionally hard on behalf of the community and been voted in by many thousands of taxpayers.

"Vandalism, graffiti and rude behaviour should not be tolerated, there is a cost associated each time someone tampers with ratepayer and taxpayer funded infrastructure."

The bust of former Prime Minister Kevin Rudd was also once draped in a dress.

A number of statues in the UK and USA have been damaged or even removed. However, there have not been many reports of such acts in Australia, until now.

Any witnesses to the vandalism or anybody with information is asked to contact Crime Stoppers on 1800 333 000.

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