VM won't go away from datastore

hi

I am running vcenter 5.1 and ESXi 5.1

Theses last days I've been using storage vMotion to arrange my Datastores...so far so good but I have 3 Datastores where I move 4 VMs to another datastore (new dastore 3 TB size)

but they still continue registered in the source Datastore where there is nothing in that old datastore: no CDROM ISO, no VMX file, all virtual disks are in the new datastore

Browsing the old datastore shows nothing related in that datastore with these VMs.

any idea what could be causing this problem where I completely move these VMs to this new Datastore but they still will show in the old one

thanks  a lot