somebody is making partial impersonation on facebook using explicit images ?

[Roopchand]

impersonation had involved only partial part of the name on facebook. but the content posted is really explicit.actually the guy involved in that matter is also very known to me, who is a colleague of us.that particular guy is undergoing some psychotic treatment.so he is making fake acounts for many of our other colleagues.he believes in faking everything as he himself is a big fake working on forged document in the company to earn a pretty good salary.
he thinks that nobody can identify him. so what am i suppossed to do deal with him -file a defamation case or report the content to facebook or teach him a lesson in his own way to make him understand well. kindly post your comments.thanks in advance.

[Going with Logic!]

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