New Delhi: Congress President Sonia Gandhi has written to Prime Minister Manmohan Singh over the suspension of IAS officer Durga Shakti Nagpal, saying the officer must not be "unfairly treated".PromotedListen to the latest songs, only on JioSaavn.comHere is the full letter:Also ReadNew Defence, Health Secretary In Top-Level Bureaucratic Reshuffle By CentreAll You Need To Know About New Thailand PM Paetongtarn Shinawatra"Natural Disasters Increasing Concerns": PM Modi On Independence Day