The report also mentioned that the victim, Rajkumar (49) also had pneumonia.
Rajkumar, a small-time financial agent was on June 12 rounded up by a group of people who he owed money to. After they realized that he was unable to repay their money, the group handed the victim over to the Nedumkandam police station.
The police however, recorded his arrest only on June 16 and was later shifted to the state-run Peerumedu Taluk Hospital where he died on June 21.
Speaking to the media after the report was released, Leader of Opposition Ramesh Chennithala said: "The principal culprit in this clear case of custodial torture is the Idukki Superindent of Police. They are now trying to hoist the cause of death on the group of people who had handed the victim over to the police.
"Also in previous cases of custodial torture, the Pinarayi Vijayan government has done everything to save police officials, leading to more and more custodial deaths. We demand a judicial probe into Rajkumar's death."
After the case came to light in the Kerala Assembly last week, the state government ordered a Crime Branch police probe and suspended four officers from the Nedumkandam Police station and transferred eight others.
Angry BJP demonstrators on Sunday marched towards the police station in protest.
Referring to the case of the 26-year-old Sreejith, who died in police custody in March, popular media critic and lawyer S. Jaisankar said there was no point in taking action against the police officials since the ones who were suspended after Sreejith's case are now back in service.
( With inputs from IANS )