Kestrel - No, it's a Sparrowhawk

We have been trying to encourage the wild birds into our garden particularly now the cats are too slow and old to bother them. I was suprised this morning to see a rare visitor however not so pleased when I realised he was eating one of the pigeons. According to the RSPB website it looks like it is a Sparrowhawk. http://www.rspb.org.uk/wildlife/birdguide/name/s/sparrowhawk/index.asp#