South Korean President Yoon Suk-yeol issued an apology to the nation over a deadly pre-Halloween crowd crush, with members of his government facing criticism over management of the incident that killed at least 156 people.

"I am sorry and apologetic to the bereaved families who are facing tragedy that cannot be expressed in words and to the people who share the pain and sorrow,” Yoon said Monday in a meeting with his Cabinet and outside experts to review national safety systems.

Yoon has also called for large-scale police reform as well as a thorough investigation into the tragedy, saying he wants to disclose to the public what happened "without a speck of doubt” and hold accountable those responsible for the incident.

The meeting comes after top South Korean officials acknowledged last week that a lack of proper crowd management probably contributed to a surge of people that caused the country’s deadliest civilian crowd crush. Yoon’s government has also faulted police for not doing enough to heed warnings that masses were growing to dangerous levels in the Itaewon nightlife district of Seoul, where about 100,000 people gathered for Halloween festivities.

Yoon, who came to office in May, is seeking to avoid the mistakes of his predecessors, who had been sometimes seen as too slow to respond to disasters. So far, it appears as though he hasn’t taken a major political hit from the Itaewon tragedy, with a weekly tracking poll from Gallup Korea on Friday showing his support dropping 1 percentage point to 29%. A Realmeter weekly tracking poll on Monday said support was at 34.2%, down 1.5 percentage points from a week before.

While Yoon is being tested at home over the crowd crush, North Korea has unleashed major provocations in the past week such as firing off its biggest barrage of missiles in a single day, including its first rocket to ever cross a nautical border with South Korea established after the 1950-1953 Korean War.

Over the weekend a crowd estimated by police of at least 9,000 people held candles at a mass rally in Seoul to mourn those who lost their loved ones. Many held placards reading "Resigning is an act of condolence,” with crowds chanting for Yoon’s government to step down.

Lee Jae-myung, the leader of the main opposition Democratic Party, called for reforms larger in scale than those proposed by Yoon and for the president’s premier to be sacked.

Some of the officials facing pressure over the incident include the interior minister and the commissioner general of the South Korean National Police Agency — both of whom were appointed by Yoon. The Seoul Metropolitan police chief and the police chief of the Yongsan ward where the incident took place have also faced criticism in local media.

Last week, a team of special investigators raided the headquarters of the Seoul police force, shortly after authorities released records of frantic emergency calls, one coming about four hours before the incident, warning that crowds of partygoers were growing dangerously large.

Those killed in the crush were trapped in an alley 3.2 meters (11 feet) wide that linked a main street in the Itaewon neighborhood to an area filled with restaurants, bars and nightclubs. There were at least 26 foreigners among those killed.

Witnesses told local media that as people squeezed into the tiny space, some began to fall, causing others to tumble and pile into one another. Most of the victims died from asphyxiation.

"The government should not only handle this disaster responsibly, but also put all-out efforts into making South Korea safe to never repeat such tragedy like this again,” Yoon said Monday.