"Unexpected element '{urn:jboss:domain:8.0)domain'" while starting domain in JBoss EAP

Issue

Encountering the failure below when starting a domain using the domain.sh script,

... ERROR [org.jboss.as.controller] (Controller Boot Thread)

... OPVDX001: Validation error in domain.xml ---------------------------------------
... |
... |  1: <?xml version='1.0' encoding='UTF-8'?>
... |  2:
... |  3: <domain xmlns="urn:jboss:domain:8.0">
... |     ^^^^ Unexpected element '{urn:jboss:domain:8.0)domain'
... |  ...
... |
... | The primary underlying error message was:
... | > ParseError at [row,col]:[3,1]
... | > Message: Unexpected element '{urn:jboss:domain:8.0)domain'
... |
...