An effective way to stop adwords ad clicking by a bot?

Some of my competitors is spending to much time to ruin my ads, my money and my business…

What makes me think that he's using an clicking bot?
as soon as my ads start to go online there are always visitor coming instantly (at any time 0-24h) through my ad to the site, spending from 1 to 5 minutes on my start-/landingpage or just clicking through my site in record time, when one visitor leaves, the next one appears in about 10 secs. after i turned my ads to only display at mobile phones it…

An effective way to stop adwords ad clicking by a bot?