Bzr crashes with BzrCheckError

[vSC]

While running bzr branch, bzr crashed. The output on terminal is below:

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vijit@vijit-laptop:~/do$ bzr branch lp:do
bzr: ERROR: bzrlib.errors.BzrCheckError: Internal check failed: Cannot add revision(s) to repository: missing referenced chk root keys: [('sha1:576fa262710cb8cadf998f50c33f4fa28ac6f57b',)]

*** Bazaar has encountered an internal error. This probably indicates a
    bug in Bazaar. You can help us fix it by filing a bug report at
        https://bugs.launchpad.net/bzr/+filebug
    attaching the crash file
        /home/vijit/.cache/crash/bzr-20100731123625-5824.crash
    and including a description of the problem.

    The crash file is plain text and you can inspect or edit it to remove
    private information.
vijit@vijit-laptop:~/do$

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