In the 1960s and early 1970s, South Korea sent troops to support America's doomed fight against the communist North Vietnamese during a bloody two-decade conflict that ended with the fall of Saigon and Vietnam's reunification in 1975.

South Korean marines were accused of killing around 70 civilians during a raid on February 12, 1968 in a case brought to court in Seoul by a Vietnamese woman who survived the massacre.

Seoul's Central District Court ruled that victim Nguyen Thi Thanh should be compensated with 30 million won ($23,800), plus interest, for the mass killings in the town of Phong Nhi in Vietnam's central Quang Nam province.

Thanh, now 62, who was injured in the raid and lost family including her mother, filed the lawsuit in 2020 seeking compensation from the South Korean government.

Over the past three years, Vietnamese witnesses and journalists who covered the 1968 incident have appeared in court to testify.

The court eventually sided with the victim, rejecting the government's argument that it was hard to prove Korean troops were the perpetrators.

Marines had "threatened the plaintiff's family with guns and took them outside to shoot them", the court said in its verdict, according to Yonhap News Agency.

"The plaintiff's mother was rounded up with others by the soldiers and shot dead... It is established that the plaintiff's families were killed on the spot", the verdict added.

The court also ruled that a 1965 agreement between Seoul and the South Vietnamese government -- which Seoul claimed made its troops immune from legal liability -- did not prevent individual Vietnamese victims from seeking compensation.

Thanh welcomed the ruling in a video released by her legal team.

"I think the spirits (of those killed in the massacre) were with me and supported me," she said. "I am so happy that the souls can now rest."

Her legal team also hailed the unprecedented verdict.

"Today's ruling bears significance that the South Korean court acknowledges for the first time that there was an illegal act committed during the Vietnam War and that the South Korean government should be held legally accountable," Thanh's attorney Lim Jae-sung said.