Human Rights Watch emergency director Peter Bouckaert told the Washington Post that he believes that Egyptian undercover police were behind the looting that took place at the Egyptian Museum "in an attempt to stoke fear of instability." See
http://www.rawstory.com/rs/2011/02/rights-group-confirms-undercover-police-loot-egyptian-museum/
Bouckart reports that police identification cards were found on several wounded looters captured at the museum.
This report is similar to another that was cited on this blog.
http://ordinarymag.blogspot.com/2011/01/egyptian-journalist-and-blogger-asserts.html