SEOUL -- About 500 students and graduates of South Korea's most prestigious university gathered late on Monday to denounce President Moon Jae-in's appointment of Cho Kuk, a scandal-hit aide, as justice minister.

"You are not qualified to be justice minister," chanted the protesters at Seoul National University. "Step down right now!"

The students were holding candles in a scene reminiscent of the 2016-17 protests that led to the impeachment and incarceration of Moon's predecessor Park Geun-hye. They expressed their anger and disappointment at the liberal Moon administration, which they had hoped would clean up the corruption and power abuse of Park's conservative government.

"[The situation] is not uncommon to me," said Kim Keun-tae, a Ph.D. candidate at the department of materials science and engineering. "I raise the candle again as I did at Gwanghwamun [Square] two years ago."

Cho is suspected of using connections to get his daughter a prestigious internship and pulling strings to help her get into a medical school. Other claims include allegations of shady family investments.

Moon pushed through the appointment of Cho despite a strong backlash from the public and opposition parties. The scandal is deepening political divisions in a country where conservatives and liberals are poles apart on many issues. It has touched a nerve among students who view college admission as the only means of upward social mobility.

"I cannot understand why it should be him?" said Lim Ji-hyun, head of students' union at engineering college. "My trust in fairness and justice has broken."

Students at other schools including Korea University and Pusan National University, alma mater of Cho's daughter, also held rallies.

Protesters hold candles as they celebrate the impeachment of South Korea's ousted leader Park Geun-hye at a rally in Seoul in March 2017. © Reuters

With Cho a potential candidate to succeed Moon, the president's supporters are mobilizing all of their resources to protect him. They also believe he is the right person to reform the prosecutorial system. A group known as the Moonlight Knights are posting positive comments on news stories about Cho, slamming opponents of his appointment as "far rightists."

A survey this week clearly showed the national division over Cho's selection. Some 49.6% of respondents to the Realmeter poll opposed the appointment, while 46.6% were in favor.

President Moon also touched on the polarized debate in the country in a speech after Cho's appointment on Monday.

"Justice Minister Cho Kuk faced many allegations, his wife was indicted, and there were fierce conflicts between those who support the appointment and who oppose it. As president, I cannot help but have deep concern watching this situation that can lead to division among people."

Prosecutors are deepening their investigation into Cho's family. Last week, they indicted Cho's wife, Chung Kyung-shim, on suspicion she forged a commendation letter her daughter received from Dongyang University, where she is a professor.

Prosecutors are also seeking an arrest warrant for Lee Sang-hoon, the head of a private equity fund into which Cho's family has invested 1.05 billion won ($881,000). They suspect Lee violated a capital markets law, and committed embezzlement.

The scandal comes as South Koreans go into the annual Chuseok, or autumn's eve, national holiday on Friday. It's an important time as family members gather to eat and talk, with the conversation often centered around politics.

"[The issue] won't end easily. Chuseok will be the moment when people will talk about this," said Shin Yul, a professor of political science at Myongji University. "It will be negative to the governing party. College admission upsets people the most. That's why opposition parties focus on this."