JEJU -- Prosecutors on Monday demanded the death penalty for a 37-year-old woman accused of brutally killing her former husband and stepson last year.

In the final hearing at the Jeju District Court, prosecutors demanded the death penalty for Koh Yu-jeong, who allegedly murdered her former husband and 5-year-old stepson in two separate incidents.

"The defendant Koh Yu-jeong murdered a father in front of a son and a son in front of her father. ... Both cases derive from her contempt towards human life and she has not shown any signs of remorse," the prosecution explained.

The prosecution cited traces of sedative found in a bloodstain made by her ex-husband and an autopsy result that suggested the deliberate murder of her stepson as evidence supporting her conviction.

Koh was indicted for killing her former husband, surnamed Kang, at a pension on the southern resort island of Jeju in May last year. She is also suspected of mutilating his body and disposing of it.

In a separate incident, she is thought to have suffocated her five-year-old stepson to death at their home in South Chungcheong Province in March 2019.

Koh has argued her ex-husband's murder was not premeditated.

She has denied killing her stepson. (Yonhap)