On the funeral day of late Seoul Mayor Park Won-soon on Monday, the main opposition party launched what is likely to become an all-out campaign to press for a probe into allegations that the deceased sexually harassed his former secretary.

The pressure by the United Future Party (UFP) highlights deepening political division over the death of the late Seoul mayor.

Park was found dead at a mountain in Seoul after apparently taking his own life on Thursday. He was facing a criminal complaint on sexual harassment, filed by his former secretary.

With Park's death, the police were to close the case against him in his absence, but opposition lawmakers are increasing calls to get to the bottom of the allegations raised against the three-term mayor who was a lawyer defending human rights and women's rights.

Two lawmakers of the minor left-wing Justice Party, deemed largely cooperative with the ruling Democratic Party, the political home of Park, refused to pay their respects at Park's funeral, saying that doing so would be tantamount to hurting the victim.

"With the closure of the funeral service, (the UFP) cannot help raising the issue involving the (sexual harassment) victim," the main opposition party's interim leader Kim Chong-in said following a party meeting.

UFP lawmaker Rep. Sung Il-jong also added pressure on the DP over the issue.

"I believe the DP, having been more proactive than anyone in the past '#MeToo' wave, would doubtlessly join the efforts to find the truth," he said, calling for a probe into the case.

Such pressure by the UFP is expected to culminate in a parliamentary confirmation hearing on National Police Agency chief nominee Kim Chang-yong, scheduled for July 20. The case against Park is likely to be the focal point during the hearing.

Releasing a statement under a parliamentary think tank, two UFP lawmakers -- Ha Tae-keung and Kim Woong -- also pressured the Ministry of Gender Equality and Family to look into the allegations involving Park.

"The ministry should investigate the sexual harassment allegations related to Mayor Park and illuminate the truth to the public," the statement said.

DP Chairman Lee Hae-chan apologized Monday over the sexual abuse accusations raised against Park.

"I give my apology for the current situation. ... I feel deeply responsible for the unexpected vacancy in the city administration," party spokesman Kang Hoon-sik quoted Lee as saying after a party meeting. Lee also expressed consolation to the alleged victim, Kang said.

Lee vowed that "the party will do its best to keep things like this from happening again."

Park was the third high-profile DP member accused of sexual assault in the #MeToo wave after former Busan Mayor Oh Keo-don resigned in April over similar accusations. In 2018, An Hee-jung stepped down as governor of South Chungcheong Province after his secretary exposed his sexual abuse. (Yonhap)