Possibly malicious location reported in who's online

[Angel-Wings]

Well - except you run vulnerable software at your Server / Site there's no need to put a lot of care about this.
Rotating IP's and Locations - typical script kiddies scanning IP ranges with a list of vulnerable software for locations to hack.
Like said - except you run vulnerable software there's no need to care about it. Also writing down the IP's trying to contact the hosters or blocking them - waste of time. Better secure your machine instead of taking care about others at first.

If an IP is getting too annoying - excessive scanning for 1 or 2 days - you can take your logs and inform the hoster but usually the hosters don't care much about such reports

If you want to clean out your logs a little bit - mod_security can help to give such scanners a 4xx / 5xx reply depending on the configuration