Missing Radishes

I had quite a few, around 20, giant radishes growing in a raised bed and was really pleased with myself.  I went outside yesterday morning to find that all but 3 radishes had gone!  What's really weird is that there is no sign of the radishes ever being there.  There are no holes is in the soil where they had been growing, no signs of an animal pulling them up or anything.  I've even had a look around the garden and there's no sign of them.  I'm completely confused.  Just to top it all off the remaining 3 radishes have been hollowed out!   

What could possibly have pinched my radishes?  I've considered the possibility of aliens!   

Hi, they were in my garden. 

I pulled a couple of radish yesterday (not yours) and they were almost hollow but there was no sign of anything having got at them from the outside.

Some radishes tend to become hollow when really too old to eat, but they don't usually run away as well!