SEOUL (AFP, THE KOREA HERALD/ASIA NEWS NETWORK) - South Korean police have identified a suspect in one of the country's most notorious serial murder cases, more than 30 years after the first of the 10 killings.

Between 1986 and 1991, more than two million police officers - a record for a single case - were mobilised to try and find the person who raped and murdered women in rural parts of Hwaseong, south of Seoul.

They investigated some 21,000 individuals and compared the fingerprints of around 20,000 more without success, and the case inspired South Korean filmmaker Bong Joon-ho's 2003 box office hit Memories Of Murder.

But using the latest forensic techniques to retrieve DNA from long-past crimes, officers have identified Lee Chun-jae, 56, as a suspect in at least three of the killings, said Gyeonggi Nambu Provincial Police Agency Superintendent General Ban Gi-soo on Thursday (Sept 19).

Samples collected from evidence including a victim's underwear matched with Lee's, the police said.

The suspect is currently serving a life sentence for raping and murdering his sister-in-law in 1994, but denies involvement in the Hwaseong murders.

As the statute of limitations on the last of the 10 murders expired in April 2006, it means that Lee will not be prosecuted for the murders, police added.

Police agency chief Bae Yong-ju said that regardless of the suspect's punishment, police have the "grave responsibility to reveal the truth for victims and their families, and for the people's right to know".

Superintendent General Ban told reporters: "I express my deep condolences to the victims and their families, as well as the Korean public, for not having been able to solve this case for a long time.

"We will do our best to discover the truth with a sense of historical responsibility."

The Hwaseong killer's victims ranged from teenagers to a woman in her 70s.