The skeletal remains of a 55-year-old man were found in the boiler room of his home in Busan on Wednesday, where they had been decomposing for seven years.
The corpse was found by the man's landlord, who was trying to locate a cracked heating pipe. The landlord said the head was found away from the body.
Police later discovered strands of the man's hair stuck to an electrical wire. Judging by the fact that there were no signs of forced entry, they believe he committed suicide.
The calendar in the home was left at November 2006, while bills dating from January, 2007 were piled up inside the home, suggesting the man took his own life in late 2006.
The man, identified only by his surname Kim, moved to the lodgings with his aging mother in 1999 and lived alone after she died in 2002. His family told police they last heard from him in 2005, when he asked for money.
Kim's brother told police he came by a couple of times but the door was locked and he thought Kim, who worked on building sites, had left for work.
A neighbor who moved next door two or three years ago thought the unit where Kim had lived was empty.
Since Kim had deposited W23 million (US$1=W1,058) in "jeonse" or Korean-style deposit lease, the landlord saw no need to meet him once he had moved in.
The house was in an unpopular neighborhood, so Kim's lease was automatically renewed every two years unless he gave notice or moved out, police said.
"Even if his decomposing body gave off a bad odor, the closed boiler room probably kept the smell from alerting the neighbors," a police spokesman said.
Each unit has its own boiler room.