SEOUL, South Korea — Prosecutors brought murder charges on Thursday against the captain and three other crew members of a ferry that capsized off South Korea’s southwest coast last month, leaving 304 people dead or missing.

Lee Jun-seok, the captain, was among 15 crew members of the 6,825-ton ferry Sewol who had been arrested on various criminal charges, including accidental homicide. They were accused of fleeing their ship while making little effort to save hundreds of passengers who had been told to stay inside the vessel. Their behavior has outraged many South Koreans.

On Thursday, while indicting the 15 crew members, prosecutors brought more serious murder charges against four of them: Mr. Lee; two ship’s mates, Kang Won-sik and Kim Young-ho; and the ferry’s chief engineer, Park Gi-ho.

Before he was jailed, Mr. Lee told reporters that he did give an order to evacuate the passengers. But it remained unclear whether such an order, even if issued, was delivered to passengers who were huddled inside the ship after the crew had repeatedly told them to stay inside the dangerously listing ferry.