Really sorry you had to experience this, Mary.
I've heard of several incidents from the UK this summer. People dozing or just sitting in their back gardens enjoying the weather and not realising their house was being ransacked because they'd left the back door unlocked or a window open.
A friend had 20+ friends round his house for a BBQ last week and left the back door open so that people could use the loo. His brother went in the house only to be knocked down by 2 guys rushing out with a haul of phones, purses etc.
Take care everyone.