A man in his 70s has been sentenced to a heavy prison term for sexually assaulting his biological daughter over 40 years and also assaulting his granddaughter.

The Daejeon District Court Cheonan Branch's 1st Criminal Division (presiding judge Jeon Gyeong-ho) sentenced a man identified as A to 25 years in prison on the 7th for violating the Special Act on the Punishment of Sexual Violence Crimes (rape by a family member).

According to the court, A began to rape his daughter B in 1985 when she was just in the second grade.

B attempted to escape several times as she grew up, but she could not escape from A. More than 270 incidents of sexual assault continued for 40 years. During this time, B underwent four pregnancies and abortions.

A also sexually assaulted C, who was born to B, before C turned 10 years old.

B, realizing that her daughter was experiencing the same pain as herself, sought help from society.

A is reported to have denied the charges in court.

However, the court found A guilty based on DNA analysis results and the consistency of the victim's testimonies.

Director General Jeon Gyeong-ho lamented, "It is appalling that such things can happen in our society," adding, "The defendant has deprived the victims of the opportunity to lead ordinary and happy lives. It seems even more tragic that the mother and daughter had to witness each other's suffering."

"Nevertheless, it is unclear whether the defendant feels any guilt as he firmly denies the crimes. A heavy sentence is warranted," he said, sentencing him to 25 years in prison.