Catkin issue - error when I am initializing a ws

edit

Never happen before but If I create a directory mkdir -p catkin_ws/src and then enter catkin build I have the following error:

emeric@emeric-desktop:~/catkin_plan_ws$ catkin build
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Profile:                     default
Extending:             [env] /opt/ros/kinetic
Workspace:                   /home/emeric
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Source Space:       [exists] /home/emeric/src
Log Space:         [missing] /home/emeric/logs
Build Space:        [exists] /home/emeric/build
Devel Space:        [exists] /home/emeric/devel
Install Space:      [unused] /home/emeric/install
DESTDIR:            [unused] None
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Devel Space Layout:          linked
Install Space Layout:        None
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Additional CMake Args:       DCMAKE_BUILT_TYPE=Release
Additional Make Args:        None
Additional catkin Make Args: None
Internal Make Job Server:    True
Cache Job Environments:      False
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Whitelisted Packages:        None
Blacklisted Packages:        None
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Workspace configuration appears valid.

NOTE: Forcing CMake to run for each package.
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Traceback (most recent call last):
  File "/usr/bin/catkin", line 9, in <module>
    load_entry_point('catkin-tools==0.4.4', 'console_scripts', 'catkin')()
  File "/usr/lib/python2.7/dist-packages/catkin_tools/commands/catkin.py", line 267, in main
    catkin_main(sysargs)
  File "/usr/lib/python2.7/dist-packages/catkin_tools/commands/catkin.py", line 262, in catkin_main
    sys.exit(args.main(args) or 0)
  File "/usr/lib/python2.7/dist-packages/catkin_tools/verbs/catkin_build/cli.py", line 420, in main
    summarize_build=opts.summarize  # Can be True, False, or None
  File "/usr/lib/python2.7/dist-packages/catkin_tools/verbs/catkin_build/build.py", line 283, in build_isolated_workspace
    workspace_packages = find_packages(context.source_space_abs, exclude_subspaces=True, warnings=[])
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/packages.py", line 86, in find_packages
    packages = find_packages_allowing_duplicates(basepath, exclude_paths=exclude_paths, exclude_subspaces=exclude_subspaces, warnings=warnings)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/packages.py", line 146, in find_packages_allowing_duplicates
    xml, filename=filename, warnings=warnings)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/package.py", line 509, in parse_package_string
    raise InvalidPackage('The manifest must contain a single "package" root tag')
catkin_pkg.package.InvalidPackage: The manifest must contain a single "package" root tag

Besides the build and devel folders are created in my home directory not in the catkin one.

I guess I messed up something but I do not what and thus how to fix it.

Thank you for your help