SEOUL, South Korea — Prime Minister Chung Hong-won, the No. 2 official in the South Korean government, apologized and offered to resign on Sunday, as the country remained angry and saddened over the sinking of a ferry that left 302 people, a vast majority of them high school students, dead or missing.

The government has come under fire as early investigations revealed a slew of loopholes in safety measures and a lax regulatory enforcement that investigators said contributed to the sinking of the 6,825-ton ferry, the Sewol, on April 16.

It was also criticized for failing to respond quickly and efficiently to the crisis and for fumbling during the early stages of rescue operations.

A somber-looking Mr. Chung accepted the criticism on Sunday when he offered “an apology to the people” during a nationally televised news conference. “When I saw the people’s sadness and fury, I thought it was natural for me to step down with an apology,” he said.