Mass delete customers in DESK

Mass delete customers in DESK

Hello community !

Fisrt question here. 
New user to DESK, I made the mistake of linking desk and CRM together.. seems somes contacts from CRM appears now on DESK but it's not wanted.

I don't find an option to mass delete them in DESK.
I can select them one by one and then delete but when there are hundreds of them it's not funny ;-)

Do you have an idea to help me ? 
Thanks in advance,

Fred