It is mind-boggling that the nation’s parliament has a member who allegedly attempted to use it as a “bridgehead for revolutionary struggle” and conspired to subvert the South Korean government through an armed revolt.

Prosecutors made these allegations against Lee Seok-ki, a first-term lawmaker of the minor opposition United Progressive Party. They submitted detailed charges against Lee, 51, to the National Assembly on Tuesday as they sought parliamentary consent for his arrest.

According to the arrest request, Lee formed the UPP and “infiltrated the National Assembly” as a proportional representative to stir up revolution and assist the North in the event of a war.

He allegedly formed an underground pro-North Korean organization, dubbed the “revolutionary organization,” to carry out an armed revolt.

According to the arrest motion, Lee convened a secret meeting of the group in May and urged its 130 members to prepare an attack, saying that North Korea had effectively declared war by withdrawing from the Korean Armistice Agreement. Pyongyang declared the cease-fire agreement null and void in March.

Lee and other leaders of the group allegedly told the participants to conduct a “speedy war” and destroy infrastructure such as oil storage facilities, power transmission towers and telecommunication centers.

The plot Lee is alleged to have drawn up sounds so surreal that one may be tempted to dismiss it. Yet if 130 people make determined efforts to destroy major facilities, they could wreak havoc on South Korean society and its economy.

Furthermore, there could be other, still unidentified underground organizations under the control of Lee.

Now, the ruling Saenuri Party and the main opposition Democratic Party need to swiftly pass Lee’s arrest consent motion. Then, the parties need to reflect on themselves as they have allowed a shady pro-North Korean figure like Lee to become a lawmaker.

In this regard, the DP deserves much of the blame as it paved the way for the UPP’s parliamentary presence by forming electoral alliance in the general elections in April last year.

At the time, some of the DP leaders were aware of the danger of joining hands with Lee’s pro-North Korea faction in the UPP. But they ignored the danger blinded by their desire to win the election.

Now, the party needs to sever ties with the UPP. DP leader Kim Han-gil said Tuesday that his party would not tolerate any forces that aim to destroy the order of South Korea’s constitutional government.

Kim’s pledge sounded hollow in light of the party’s track record. As recently as last month, the party’s lawmakers mingled with UPP members at candlelight vigils held to denounce the National Intelligence Office for its alleged meddling in the December presidential election.

According to prosecutors, Lee told the May meeting of the revolutionary organization to use the ongoing candlelight vigils against the NIS as an important means of subverting the Seoul government. He hoped the vigils would grow to the size of the anti-U.S. beef rallies of 2008.

The crackdown on Lee and his followers should serve as an occasion to uproot pro-North Korea forces in the South. According to an estimate, there are some 20,000 pro-North Korean people here. They have managed to work their way into the political circle, public agencies and every field of Korean society. There should be concerted efforts to locate and eradicate them.