With the latest Harry Potter adventure, "Harry Potter And The Half-blood Prince", set for release July 16 author J.K. Rowling has warned fans to beware of imposters pretending to be her on the Internet.

Rowling has used her own website to urge fans to ignore comments posted on other Harry Potter sites - for fears they could be manipulated, reports celebrity portal Femalefirst.

"I never post on fan sites and it is important you all know this because the last thing I want is for any of you to be mislead by someone posing as me online," Rowling, who has written the six-series bestseller, was quoted as saying.