The mother of late Cpl. Chae Su-geun, who was killed during a search mission in a stream for victims of record downpours last year, submitted a petition to the police calling for the punishment of his commanders.

According to the bereaved family of the deceased marine, the mother holds the commanders responsible for her son's death while on duty. She reportedly requested police to investigate why Chae had not been wearing a life vest or other safety gear during the mission, and had been told to wear boots, which made it difficult for him to walk in the sandy stream swollen with floodwater.

The content of the petition will be discussed by the investigation committee of the Gyeongbuk Provincial Police Agency, which has been handling the probe related to the case. The police is expected to reveal the results of its investigation sometime next week.

Chae, who was a 20-year-old conscripted soldier of the Marine Corps' 1st Division, was part of the marine unit that was deployed to Yecheon, North Gyeongsang Province during heavy downpours that hit the country last summer. A total of 119 other soldiers were sent to the stream the morning of July 19 to search for those who gone missing in the flood, when Chae and two others were swept away by the flood waters.

He was found dead that night, and Republic of Korea Marine Corps wrapped up an investigation in just one week without punishment to any of his commanders.

But the case sparked a major political scandal when suspicions rose of President Yoon Suk Yeol ordering the military to scale down the investigation related to Chae's death.

The main opposition Democratic Party has been seeking to pass a bill mandating a special counsel investigation into the military response to the incident, but Yoon and the ruling People Power Party have been adamantly against it.