Manually ITM is created and when deleted manually via REST using url : http://10.183.254.160:8181/restconf/config/itm:transport-zones/transport-zone/zone name/ its observed that , even after deletion , the ietf interface operational , network topology operational and OVS retain tunnel information as seen in the dump.
The similar case is seen in Automation also. PFA of the logs with Url dumps and the Karaf log .

the build tested is for ODL master - distribution-karaf-0.5.0-20160522.153800-2438.tar.gz downloaded from - https://nexus.opendaylight.org/content/repositories/opendaylight.snapshot/org/opendaylight/integration/distribution-karaf/0.5.0-SNAPSHOT/ .