Just got a reply from head office. They referred me back to Arriva Malta.
This was my response to that:
Dear Karen, I have already contacted them myself but wanted to let you know about this also.
This is not an isolated case of blatant racial discrimination that we see so often here.
I thought that some at Arriva's parent company head office should know as with Malta having so many international visitors each year these incidents, apart from being illegal,
could seriously damage Arriva's reputation worldwide.
Especially if the parent company was to take no responsibility.