Jeong Nam-kyu committed murder, robbery, assault and rape
One of South Korea's most prolific mass murderers has killed himself while on death row.
The Justice Ministry said Jeong Nam-kyu died in hospital on Sunday - a day after being found hanging in his cell.
In 2007, the 40-year-old was convicted of murdering 13 people and robbing, raping and assaulting 20 others during a two year spree.
Although South Korea still has the death penalty, it has not carried out an execution in 12 years.
In a statement, the ministry said Jeong is thought to have died from a heart attack or brain injuries resulting from what is believed to be his suicide attempt.
He was found guilty on a range of charges from 2004 including mass murder, robbery, assault and rape.
He is believed to have left a note indicating he was worried about his execution, the Associated Press news agency reported.
No will has been discovered, although reports say the note said: "Life is like a cloud."
The last execution in the country took place in 1997.
The following year Kim Dae-jung, who was sentenced to death under the country's military rulers in 1980 before being pardoned, took office as president.