How can I remove iCloud from previous user via itunes?

I have an iPhone 6s that still has someone elses iCloud on it. It has been factory reset and I can't set it up without the old iCloud account. How can I remove it?

Sounds like you stole an iPhone. THIEF!

You need them to log you out. No other way around it,. You can try Apple but I have seen nobody get it done. Contact the original owner and have them disable it.

Yes you can unlock it

Ignore these people, you can get the iphone unlocked you gotta pay tho