Police have said that the 24-year-old who was found dead in Henveyru Annaarumaage on 1 April has tested positive for two types of drugs.
Police said that tests have shown that there were high concentrations of opium and benzodiazepine in his urine.
The case was reported by the family of the deceased at 9:15 a.m. on 1 April, said the police.
The case is under investigation by the Serious and Organised Crime Department of the police.