He said, "Oh, sorry - it's nothing like that. I should be at the empty one." Then he zipped up his fly and hopped over the fence into the nextdoor neighbour's yard.
I phoned the police.
Two nice young constables, Jeff and Rob, arrived and scouted out the place - no stange guy to be seen.
I made a statement and signed a form. Constable Jeff said it's not likely he'll come back, but that I did very well at recounting all the details I could remember.
Now I am at work, and I don't want to be at home by myself ever again.