What's with the Bots?

Hello, I have recently got a ton of Friend Requests from bots, that add you, PM you an advertisement (Usually for rulebreaking purposes such as Gameboosting/Purchasing Accounts) and then delete you.

I'm just wondering, is there any way we can report these accounts for what they're doing? I really don't think Riot would appreciate bots adding random accounts and messaging them about "Purchasing Master League Accounts!!"

Thanks :)