The Seoul city government said Friday it plans to hold a mayoral funeral for Park Won-soon and run on a contingency plan for the time being following the abrupt death of the liberal heavyweight and three-term mayor.

Park, 64, was found dead in the woods of Mount Bugak near his official residence in central Seoul, shortly after midnight. Police said there were no signs of foul play, adding they plan to investigate the exact cause of his death.

His body was found after an hourslong search involving hundreds of police and rescue workers, sniffer dogs and drones. He was first reported missing by his daughter Thursday evening, who said he left a message "sounding like a will" before he vanished.

The city government pledged to carry on with city affairs in respect of Park.

"We pray for the soul of the deceased and extend our deepest condolences to the citizens (of Seoul). City affairs will firmly continue according to Mayor Park Won-soon's values that prioritized stability and welfare," Vice Mayor for Administrative Affairs Seo Jeong-hyup said in sorrow during the city's first press briefing following Park's death.

Seo will serve as the city's acting mayor until a new mayor is elected in a by-election scheduled for April 2021.

City officials said that Park's funeral will be held in the fashion of a mayoral funeral for five days. Funerals in Korea are generally last for three days.

An altar will be set up in front of City Hall in central Seoul this afternoon for citizens and staff members wanting to mourn Park's death, they added.

The mayor was reportedly facing a probe into allegations of sexual harassment. A female former secretary is believed to have filed a criminal complaint on Wednesday over unwanted "physical contact" and "inappropriate" messages.

Police officials declined to elaborate on the case, including whether the complaint was submitted.

In accordance with the law, the case was automatically terminated upon the mayor's death.

When asked whether the city plans to open an investigation, city officials said they are "not yet aware" of the allegations and have not reviewed such plan.

Park was regarded as a presidential hopeful for the ruling Democratic Party in the 2022 elections.

The civic activist and human rights lawyer was first elected in a 2011 by-election and re-elected in 2014 and 2018. His term was slated to end in 2022.

As the longest-serving mayor for the country's biggest city, where one-fifth of South Koreans live, his policies centered on youth, environment and urban regeneration. (Yonhap)