Park's denunciation, in which she vowed to hold all those responsible for the disaster "criminally accountable," followed the release of a transcript showing the panic and indecision that paralyzed decision-making on the bridge as the 6,825-tonne Sewol listed and capsized on Wednesday morning.
The confirmed death toll stood at 64 but was expected to rise dramatically with 238 people still unaccounted for.
"The actions of the captain and some crew members were utterly incomprehensible, unacceptable and tantamount to murder," the presidential Blue House quoted Park as saying in a meeting with senior aides.
"Not only my heart, but the hearts of all South Koreans have been broken and filled with shock and anger," said Park, who had been heckled on Thursday when she met relatives of the hundreds of passengers still missing -- most of them schoolchildren.
The families have criticized the official response to the disaster, saying the initial rescue effort was inadequate and mismanaged. The president said it was increasingly clear that Captain Lee Joon-Seok had unnecessarily delayed the evacuation of passengers as the ferry started sinking, and then "deserted them" by escaping with most of his crew members.
"This is utterly unimaginable, legally and ethically," she said.
Lee was arrested on Saturday along with a helmsman and the ship's relatively inexperienced third officer, who was in charge of the bridge when the ship first ran into trouble.
A transcript released on Sunday of the final radio communications between the Sewol and marine transport control underlined the confusion that reined as the vessel listed sharply to one side after making a distress call.
Marine control ordered the crew to ensure all passengers were wearing life jackets, while the ship repeatedly questioned whether vessels were on hand to rescue people once they started to abandon ship.
"Make them wear a life ring at least and let them float. Now!" the control official insisted.
In the end, the evacuation order was only given around 40 minutes after the ship ran into trouble, by which time it was listing so heavily that escape was almost impossible.
"Precious minutes just wasted," was the front page verdict of the Dong-A Ilbo daily on Monday.


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