Is it safe to delete all .deb files under "/var/cache/apt"?

[Lian Liming <lianliming@gmail.com>]

Dear all,
 
     I find my space for "/" partition have little space left. So I want to delete some un-useful files.

     It seems all my installed packages' deb files
locate under "/var/cache/apt". I *guess* those files should not be
necessary to my current system. So I want to delete them to release
some spaces.

     So I wonder if it is  safe to delete all .deb files under "/var/cache/apt"?

     Thanks in advance!

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