Specifically, Sewol sank on April 16, 2014. It is believed to be South Korea’s deadliest maritime casualty since 1970, which resulted to 304 passengers losing their lives and 172 rescued. Notably, the 254 of the deceased were secondary school students and teachers from Danwon High School (Ansan City).

Today, South Korea's prosecution will set a special unit to investigate the vessel's sinking, a move which was instructed by Prosecutor General Yoon Seok-youl.

The team that will conduct the investigation is expected to look into suspicions raised by families of the victims.

As the disaster's legacy is closely intertwined with Korean politics, the launch of a new criminal investigation has raised speculation about possibility of political motivations. Lim Gwan-hyeok, the prosecutor heading up the inquiry, reported these concerns in recent interviews.

Concluding, following an investigation that took place after the incident, Lee Sang-Yun, a professor and one of South Korea's leading marine engineers, concluded that many risk elements caused the accident in stages: unqualified personnel, passing Maengol with the strong current in fast speed, overloading, the shortage of ship ballast equilibrium water, lack of a national integrated disaster prevention system, and others.