Butterly, Moth or Hornet?

[Redrum]

While gardening today, i noticed a lump of wood sticking out on my fence, upon prizing it off it broke open and inside was a large dark brown pupae which was encased within, next to this was some obvious fence damage where it had made its cocoon from the wood....can somone have any idea what this was - it was on its own no others near it, it looked to me like a hornet pupae but no idea on their lfe cycle.

[poodicat]

Could be a wood wasp huge buggars