A man convicted of killing his female co-worker at a subway women's bathroom in Seoul has been given a life sentence by an appeals court.

The Seoul High Court on Tuesday handed down the life sentence to Jeon Joo-hwan who was indicted on charges of “revenge killing” and stalking. 

In issuing the ruling, the court said crimes of retaliatory nature require stern punishment as they cripple the criminal justice system. It added that Jeon committed the act of murder in an extremely premeditated and thorough manner. 

Jeon, a former employee of the Seoul Metro, is accused of stabbing his co-worker in her 20s to death in a restroom at Sindang Station on Seoul Metro Line Two last September. He committed the murder a day before a court was set to sentence him on charges of stalking and harassing the victim.

The latest verdict came after the appeals court combined the stalking and murder charges against Jeon. In the first hearings, courts had sentenced Jeon to nine years for stalking and 40 years for murder.

The latest ruling is lighter than the death penalty sought by the prosecution.