When to evict tenants in newly purchased REO ?

[Christie Gahan]

Just signed PSA for a bankowned duplex that has folks living there.    My understanding is that , while I'm in escrow, I don't own it.   So, I don't really have a right to get them out.  But, they don't really have the right to be living there either.  Any one have this problem in the past ?  Should I communicate with them now ?  Or, wait until closing and then start evictions ?  Cash for keys ?  Thanks.