SYDNEY - Police in Australia are urging teenagers to guard themselves against online predators after a teenager was lured to her death last week.

Nona Belomesoff, 18, was found dead in isolated bushland southwest of Sydney after going to meet a man she met on Facebook who offered her a fake job protecting wildlife.

Police have charged a 20-year-old man with her murder.

They say Belomesoff believed she was also meeting a second man but he did not exist.

Detective Superintendent Peter Crawford of Queensland's Task Force Argos, which targets online predators, said there was no reason a teenager or a child should have a photo on their Facebook profile page.

"If you use social networking as a closed networking with friends that you know ... then the risks are very much reduced," he told ABC Radio.

Belomesoff's brother Gary, 20, said his sister told the family she had been offered work with the New South Wales Wildlife Information Rescue and Education Service.

"He said he could get her a job," he said. "She loved animals and saw this as an opportunity to follow her dream.

"She said she was going camping to look for injured animals. Nona said if she didn't go she would lose her job and this job was her dream. So she just went and that was the last time we saw her."

Crawford said posting personal information exposed internet users to a range of dangers.

"If you post private information ... you are leaving yourself very much exposed, not just to these types of offences, but also to fraud."

Every month, the police task force received at least one complaint relating to online offenders, but police posing as children online could be hit upon regularly, he said.

Police are advising young people to remove their profile pictures and personal details from Facebook.

- Agencies