A group of officers based at a central Japan police station are expected to be referred to prosecutors over allegations they failed to make adequate medical care available to a detained man who suffered chronic diseases, leading to his death late last year, an investigative source said Tuesday.

The case of the 43-year-old man is being investigated as professional negligence resulting in death. The Aichi Prefectural Police are making arrangements to send investigative papers to prosecutors detailing the allegations against the officers from the police station in the city of Okazaki who were in charge of detention cells.

The chief of the Okazaki police station is unlikely to face charges due to the apparent difficulty of foreseeing the man's death, according to the source.

The man was arrested on Nov. 25 last year for allegedly obstructing official duties and died in a police cell on Dec. 4 from kidney failure, according to an autopsy. He was battling diabetes and schizophrenia at the time.

The man had been placed in solitary confinement as a result of violent behavior and restraining devices were used on him for more than 130 hours. He was not given access to medicine for his chronic illnesses, nor provided medical assistance even though he was refusing meals.

Security camera footage also showed the man being apparently kicked, with those allegedly involved in the attack also possibly set to be referred to prosecutors for assault by police and judicial officials.

The assault is unlikely to have any causal connection with the death of the man, according to the source.

The prefectural police searched the Okazaki police station in December and have been questioning officers based there.