First pictures of Britney Spears' baby boy have been leaked on the Internet, but were quickly removed after she threatened legal action.

The six thumbnail shots of Spears, husband Kevin Federline and their baby Sean Preston were published at www.tanglebrit.com but have now been removed.

"Anyone who publishes, sells or otherwise exploits any of these images in any way will be subject to liability and damages for wilful infringement of copyright," said Spears' attorneys.

Apparently, the photographs were taken by Mark Liddell for a photoshoot for People magazine, although the publication has said it did not authorise the photos.