South Korean police detained a man who rammed a large excavator into a gate Tuesday near the office where prosecutors questioned a woman at the center of a scandal that threatens the country's president. The woman had earlier said she "deserves death" and the detained man said he "came here to help her die."

The attack with heavy construction equipment on a government building is part of a frenzy of emotion in South Korea over the woman, Choi Soon-sil, whom prosecutors have detained as they examine whether she used her close ties to President Park Geun-hye to pull government strings from the shadows and amass an illicit fortune.

Prosecutors are expected to quickly seek an arrest warrant for Choi, who was swarmed Monday by hundreds of journalists and protesters as she tried to enter the prosecution office.

Choi, a cult leader's daughter with a decades-long connection to Park, was nearly knocked off her feet several times as the crowd closed in on her. Protesters screamed for her arrest and Park's resignation; one angry person reportedly tried to enter the building with a bucket full of animal feces; and Choi, 60, lost her Prada shoe in the scrum.

Social media is now awash with images of the discarded black footwear and the word, "Soonderella," a combination of parts of Choi's name and the girl from the fairy tale who leaves behind a glass slipper at a ball.

"Please, forgive me," Choi said Monday through tears inside the Seoul prosecutor's building. Using a common expression of deep repentance, she added, "I committed a sin that deserves death."

The man accused of running his big yellow excavator into the prosecution office near where Choi had been investigated later told officials that "since Choi Soon-sil said she committed a sin that deserves death, I came here to help her die," according to police officer Han Jeung-sub. The man detained was identified as a 45-year-old surnamed Jeong.

It wasn't known if Choi was at the Seoul office at the time of the ramming, which injured a security guard and damaged the gate and other facilities.

Last week, amid intense speculation, Park acknowledged Choi had edited some of her speeches and provided public relations help. Widespread reports have said Choi had a larger role in government affairs despite having no official ties to the administration.

Prosecutors are trying to determine the scope of access Choi had and whether she was given sensitive presidential documents. Choi has previously said she helped Park but didn't know if she was seeing confidential information.

Other reports have contained allegations she misused money from nonprofit organizations after pressuring businesses to donate to them.

Park has fired some of her closest aides to try to contain the fallout. Some lawmakers and the public have called for Park's resignation or impeachment, and thousands of people have protested in the streets.

Choi has been close to Park since Choi's father, the leader of a religious cult, gained Park's trust by reportedly convincing her that he could communicate with her assassinated mother. Choi's father denied this in a 1990 media interview.

The scandal has resonated with South Koreans in a way that past corruption allegations have not.

Some of this has to do with Park Geun-hye, who has long been criticized for an aloof manner and for relying on only a few longtime confidantes. That she may have been outsourcing sensitive decisions to someone outside of government, and someone connected with a murky, lurid backstory, has incensed many.