Bhubaneswar, Feb 3 (IANS): Even though four days have passed since the murder of Odisha Health Minister Naba Das, the Odisha police are yet to reveal the motive behind the brutal killing.

To recall, assistant sub-inspector Gopal Krishna Das had shot Naba Das in Jharsuguda district on January 29. Later the same day, the minister had succumbed to his injuries.

Soon after the incident, Gopal Das was arrested and the crime branch took over the case. The crime branch officials have been interrogating Gopal Das and his family members since then. However, the police are yet to reveal the motive behind the murder.

In a press statement issued on Thursday evening, the crime branch said that it has recovered one bullet which is a valuable piece of evidence.

Following the lead given by the ASI during interrogation, the crime branch recovered some pieces of handwritten papers of the accused from the septic tank attached to the toilet of Airport police station in Jharsuguda.

The accused told the police about dumping handwritten papers, in which he had noted down in detail his motive behind the crime, in the toilet of the Airport police station. The paper pieces will be sent to forensic and handwriting experts for reconstruction and examination, the crime branch said.

The preserved viscera of the deceased has been sent to the state forensic science laboratory (SFSL) in Bhubaneswar for examination, it said.

Similarly, another team of crime branch is verifying the medical treatment records and financial behaviour of Gopal Das, besides examining the near and dear ones of the accused. Earlier, the elder brother of the accused ASI was interrogated.