The captain of a South Korean ferry that capsized three days ago, leaving 28 people confirmed dead and 268 missing, was arrested early on Saturday, Yonhap news agency reported.
Lee Joon-Seok faces five charges, including negligence of duty and violation of maritime law, the agency said.
The move comes after it emerged that a junior officer was at the helm at the time of the sinking of the ferry on Wednesday that has claimed at least 28 lives and left 268 others missing.
Yonhap said a local court in Mokpo had issued warrants for him and two other crew members, citing the possibility that they may flee or destroy evidence, AFP news agency reported.
"The captain was not in command when the accident took place," state prosecutor Park Jae-Eok told a press briefing on preliminary findings of the investigation into the disaster.
Of 475 passengers and crew on the Sewol ferry 179 people were listed as safe and 268 were still missing.
The investigation into South Korea's ferry disaster focused on the sharp turn it took just before it began listing and on the possibility that a quicker evacuation order by the captain could have saved lives, officials said on Friday, as rescuers struggled to find some 270 people still missing and feared dead.
Police said a high school vice principal who had been rescued from the ferry was found hanging Friday from a pine tree on Jindo, an island near the sunken ship where survivors have been housed.
He was the leader of a group of 323 students travelling on the ship on a school excursion, and said in a suicide note that he felt guilty for being alive while more than 200 of his students were missing.
Rescue teams were finally able to get inside the ferry on Friday but were still unable to reach the area where it is hoped survivors may be in an air pocket.
How could he tell those young kids to stay there and jump from the sinking ship himself?
The vessel started to sink during a routine trip out of the major port of Incheon to the holiday island of Jeju, 480km to the south.
Coastguard officials have said the investigation was focused on possible crew negligence, problems with cargo stowage and structural defects of the vessel, although the ship appears to have passed all of its safety and insurance checks.
Relatives of those who died have accused the captain and some of his crew of being among the first to leave the vessel.
Both 69-year-old Lee and the company that owns the ship have apologised for the loss of life, although neither has admitted responsibility.
Most of those on board were children from a high school in the suburbs of Seoul who were on a field trip to Jeju.
Relatives were in mourning overnight in a hospital in the city of Mokpo, close to the port city of Jindo, which is acting as a rescue centre.
Some of them spoke bitterly of the captain.
"How could he tell those young kids to stay there and jump from the sinking ship himself?" said Ham Young-ho, grandfather of 17-year-old Lee Da-woon, one of the dead.
Lee has not made any public statement on whether or why he may have left the vessel before many of the passengers.