However, you have to make sure that you have removed the vector they used to attack as well as the symptoms of the attack, or it will just happen again.
How is this done?
The “only” thing happened is that malicious files was added to my account so that the website got blacklisted from google. No content was changed or anything like that (i have several sites hosted on the same account, so its possible that one of the other pages was the security issue).