Author JK Rowling, has revealed one of her characters will be killed off in the next Harry Potter book.

But she kept fans guessing over which one of them will die.

Rowling was asked on her website: "Are you going to kill off any more characters?"

She replied: "Yes, sorry."

The sixth book, Harry Potter And The Half-Blood Prince, is due to be published next year.

Fans can be reassured that the schoolboy wizard himself is safe. Rowling said earlier this year Harry will definitely survive to the seventh and final book.