beside the large painted marks on the roofs/etc., on Ukranian TV 10 minutes ago they shown some marks which are kind of plastic stick-on 1 inch square with the same cross-in-circle image. The stick-on are reflective and have numbers. Some people think it is a mark of the houses with police, military residents, etc...
looks like it. There had some time ago been warning that some civil markers may be mistaken for suspicious one, and looks like that is what happening in this case. Sent them email about these ones.
