A security guard noticed a foul smell coming from the unit and alerted police last night, The Star Online reported today.
Police kicked down the door and found the man lying face down on the bed, showing traces of blood. He is believed to have been dead for at least four days.
According to documents found inside the apartment, the man was 43 years old and from South Korea.
The man is believed to have rented the unit since May last year. He was in Malaysia to learn English.
A post-mortem confirmed the cause of death as “intracranial bleeding with underlying coronary artery disease” or heart attack.
Police said the man was last seen by his neighbours two weeks ago.
Sentul district police chief ACP R Munusamy said the apartment was locked from the inside.
“The forensics team found no signs of forced entry and no exterior injuries on the body. Personal effects of the victim were intact.”
Munusamy said investigations suggested that the blood found around the body was due to decomposition.
“The South Korean embassy will be informed to trace his family,” Munusamy said.