Police are deeply concerned that racial violence like that of the 2005 Cronulla riots could erupt this weekend, in response to last Saturday's Muslim demonstration in Sydney.

7.30 has revealed that white-pride groups are growing online, with a series of online and text messages showing planned retaliation.

Provocative messages have begun to appear on Facebook pages, calling on white "home-grown" Australians to respond violently to protests.

On Wednesday night, the following text message found its way online, urging non-Muslim Australians in Victoria to unite and fight back at a planned pro-Muslim protest in Melbourne this weekend:

"Let's show these bearded goat-herders that we run this country, not them and if they don't like it, they can f*** off back to whatever s***hole they came from on the leaky boat they showed up on. Spread the word and come ready for a battle for our rights and our land. They thought Cronulla riots were bad. We grew there, they flew there! Australians unite!"

Victoria's Deputy Police Commissioner Tim Cartwright says he found the text message "disgusting".

"I found that text message itself quite disturbing. Probably disgusting would be a strong enough word to say how I found that. There is nothing to indicate that we'll have any sort of riots in this city," he said.

Other messages posted online are just as vitriolic.

"If these Muslims wanna riot and ruin our beautiful city over some stupid b***s**t, we will give them a f***ing riot to remember," said one message.

Another read: "F*** them off. This is Australia, not f***ing Muslim land. Fight back if they start again."

It is the reference to the Cronulla riots that has Victorian police on high alert.

A virtual flyer has begun to circulate among young Muslims online, calling for them to join a peaceful march this weekend.

Late yesterday afternoon, controversial Islamic group Ahlu Sunna Waljama entered the storm with a text message urging its own to boycott the pro-Muslim protest.

"For any Muslim who is planning to protest on Sunday, it is ill advised. The Muslim community is already under enough scrutiny," the text read.

Police prepared

In New South Wales, the authorities are bracing for a wave of anti-Muslim retaliation.

The state's Deputy Police Commissioner, Nick Kaldas, says authorities will be prepared but they are not aware of any "specific plans or threats".

"There's always potential for a group of like-minded people to gather each other up through social media, but we're asking them to be sensible and think about the consequences of your actions," he said.

The United States consulate has issued a warning to its citizens to avoid Sydney and Melbourne CBD areas this weekend.

An emergency message issued yesterday says New South Wales and Victorian Police have warned of the possibility of anti-American protests which the consulate says could turn violent.

Nine people have now been charged over Saturday's protest after a 19-year-old man was arrested in Belfield, in Sydney's south-west yesterday.

The man has been charged with a range of offences, which include throwing missiles at police.

Earlier in the day, police and Sydney's Islamic leaders joined forces to call for calm amid fears of more violent protests.