Why `edit-node` command failed with error: " Failed to mount '/dev/loop1' to '/var/tmp/edit-liveos-WcSb28/tmp-jdm2VZ'" in Red Hat Enterprise Linux 6.x ?

Issue

• While running edit-node to modify the rhevh-7.2-20160627.3.el6ev.iso to include additional packages, it fails as follows:

$ edit-node -dv --print-version /usr/share/rhev-hypervisor/rhevh-latest-7.iso 

/usr/share/rhev-hypervisor/rhevh-latest-7.iso
Losetup add /dev/loop0 mapping to /usr/share/rhev-hypervisor/rhevh-latest-7.iso
Mounting /dev/loop0 at /var/tmp/edit-liveos-WcSb28/tmp-KQ_GKp
Losetup add /dev/loop1 mapping to /var/tmp/edit-liveos-WcSb28/tmp-KQ_GKp/LiveOS/squashfs.img
Mounting /dev/loop1 at /var/tmp/edit-liveos-WcSb28/tmp-jdm2VZ
mount: wrong fs type, bad option, bad superblock on /dev/loop1,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

/usr/lib/python2.6/site-packages/imgcreate/errors.py:40: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  return str(self.message)
Losetup remove /dev/loop1
Unmounting directory /var/tmp/edit-liveos-WcSb28/tmp-KQ_GKp
Losetup remove /dev/loop0
/usr/lib/python2.6/site-packages/imgcreate/errors.py:45: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  return unicode(self.message)
Error editing LiveOS : Failed to loopback mount squashfs.img from '/usr/share/rhev-hypervisor/rhevh-latest-7.iso' : Failed to mount '/dev/loop1' to '/var/tmp/edit-liveos-WcSb28/tmp-jdm2VZ'