Two staffers of the National Institute of Mental Health (NIMH) in Mulleriyawa have been arrested over the death of a patient.Accordingly, two assistant health workers were arrested this evening (28 July), following the death of a patient under treatment at the NIMH.The 48-year-old patient is believed to have been suffering from bipolar disorder, and had been admitted to Ward 08 of the NIMH on 20 July, sources revealed.Earlier this week, however, he had reportedly succumbed to injuries sustained following an assault by NMIH staffers, while they were allegedly attempting to restrain the patient.