South Korea's prime minister has tendered his resignation amid widespread anger over the country's response to a ferry disaster that has taken hundreds of young lives and opened a painful season of soul-searching.

"I'd like to apologize for the mishandling of a slew of problems, from preventive measures before the accident to the government's initial response and follow-up steps over the accident," Chung Hong-won said Sunday. The South Korean prime minister wields few executive powers, but Mr. Chung had played a key role in coordinating the government response to the sinking of the Sewol, a ferry with 476 people on board, most of them high school students.

As of Sunday afternoon, 187 had been confirmed dead, with another 115 still missing.

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The prime minister's resignation underscored the convulsions the disaster has wrought on Korea, which has been gripped by mourning, and a rage that has taken a growing political tone. The country's chief opposition New Politics Alliance for Democracy party lashed out at Mr. Chung, calling his offer to step down "not only utterly irresponsible but also cowardly," and saying President Park Geun-hye should also apologize.

The resignation comes amid mounting pressure on Ms. Park, who has seen a near 20-point decline in approval ratings over the past week.

"Most importantly, it is an acknowledgement that government is responsible," said Chung-in Moon, a political science professor at Yonsei University. He is a former presidential advisor who currently advises the country's National Security Council. "Equally important is that it can be seen as a damage control measure to save President Park's political reputation," particularly with nation-wide local elections planned for June 4.

Mr. Chung's departure also suggests the government's efforts to blame bureaucrats have "backfired," Mr. Moon said.

The ferry disaster "has been a total failure — failure of regulation and inspection, failure of crisis management, failure of leadership and coordination and failure of trust," he said. "I strongly believe that lots of lives could have been saved if the government had come up with effective crisis management."

The government has been criticized for poor coordination that led to initial reports of survivor numbers that proved wildly inaccurate. Though divers had to work in near-blindness in waters churned by fast currents, some also faulted government for not acting quickly enough. The mix-ups have continued, with recent revelations that bodies of some students have been sent to the wrong families.

Political authorities, for their part, have moved with speed to affix responsibility to others. Last week, Mr. Park likened the actions of the captain to "murder," after numerous ferry passengers reported being told to stay on the ship, even as top crew quickly evacuated. The entire 15-member navigational crew has now been arrested. The ferry owner, too, has come under close scrutiny, with officials saying they are looking into the possibility the ship was severely over-loaded, and its ownership company had engaged in tax evasion and illegal foreign currency trading.

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Last week, Mr. Chung led calls for creation of an "innovative safety master plan," that would feature a blitz of safety audits followed by a government-wide effort to draft new rules and safety measures. Other industries have already been caught in the cross-fire, with government promising punishment for Asiana Airlines after its pilots continued with a recent flight despite discovering an engine problem.

But government efforts have done little to shield it from criticism. Last week, Woo Won-shik, with the New Politics Alliance for Democracy opposition, accused the country's leadership of incompetence. "It is not only the ferry Sewol that sank. The government's disaster management system sank too," he said. The Joongang Ilbo newspaper, meanwhile, offered a note of national despair. "A nation's standards and capability is tested when disaster and crisis come by," the paper wrote in a recent editorial. "Our country's level is a failing grade and of a third-class country."

In echoes of the U.S. after the Sept. 11 attacks, the disaster has upended normal life, in what has been called an "unofficial moratorium on fun." Cheering has been muted at baseball games and field trips cancelled for schools. Comedy shows like SNL Korea have been cancelled, as have music and sitcom programs. A movie release date was delayed, as people stay away from theatres. Some K-pop stars have halted publicity work. One singer who did proceed with a concert was heavily criticized, as was a politician who ran in a marathon.

In an editorial, one Seoul newspaper said "a majority of the general public is suffering from mental shock, sadness, rage, and feeling of helplessness."

Mr. Moon, the former presidential advisor, said the anguish stems not just from loss, but from a reevaluation of a country that has been seen, both inside and outside its borders, as a triumph of Asian innovation and economic progress.

"The disaster has also made South Koreans realize that South Korea is not necessarily a success story and that it is full of holes, defects, weakness, and backwardness," he said.