Well there is no lone working there is always a partner at the premises. This incident happened after work on her way home.
The premises have controlled access and cctv monitoring of the reception area.
Just a further note: We are singing teachers and music studios. The employee in question loves her job and loves working here as she is a musician and the job allows her free studio time and many other perks. She often in the past remained after work until midnight to practise and use the recording facilities.
We have tried (repeatedly) to get her to work the day-shift but she does dog-walking in the day and can only do evenings.