I found a trojan in my friends computer that deployed a miner mining in your pool.

"background worker.exe" --algorithm x11 -o stratum+tcp://europe1.darkcoin.miningpoolhub.com:20465 -u SantiagoMartinez.1 -p x -I d --gl 20
https://www.virustotal.com/en/file/958012ff048bf669d317c163433132c4596b5ca97a3a60ceba2e8d28c5ce9a3b/analysis/

Confiscate his coins.