'Nut rage' daughter under fire in South Korea for allegedly mistreating workers, evading taxes and smuggling luxury goods Family members of Korean Air owner Cho Yang-ho have come under heavy scrutiny.

SEOUL, South Korea -- Family members of Korean Air owner Cho Yang-ho have come under heavy scrutiny in South Korea over a series of allegedly illegal actions including charges of mistreating workers, tax evasion, and smuggling luxury goods.

The family’s elder daughter Cho Hyun-ah, known for her "nut rage" tantrum that sparked public outcry nearly four years ago, bowed deeply -- a customary action before addressing officials -- in front of scores of journalists on Thursday. Cho, who also goes by English name Heather Cho, was on her way to be questioned by Korea Immigration Service in Seoul for hiring illegal maids from the Philippines.

Cho, together with her mother Lee Myung-Hee, has been charged with illegally recruiting more than a dozen workers in the Philippines through Korean Air's Manila office, then transferring them to Seoul disguised as trainees for the company. Under the South Korean law, only foreigners of Korean heritage or foreign spouses of Korean nationals with appropriate visas could work as housekeepers.

Cho had nearly stopped a Korean Air flight leaving John F. Kennedy International Airport in 2014 over the way macadamia nuts were served -- which was supposed to be on a plate, not in wrappers. She had been imprisoned for several months over the case, then later released in May 2015 after the higher court suspended her sentence.

Her younger sister Emily Cho, or Cho Hyun-min, lit a fire on a series of police investigations on the family members of Korean Air after one of her employees posted audio recordings on the internet of her outrage at the office in March. She was summoned by police last month for allegedly hurling a beverage at a business partner in anger during an advertisement group business meeting. The victims did not seek punishment on Emily Cho but the prosecutor's office is investigating the situation on possible charges of business obstruction.

Both sisters resigned from their executive positions in April after public criticism over their behaviors.

Their mother, and Korean Air owner’s wife, Lee, 69, has also allegedly mistreated and abused her private driver, security guards at home, and several laborers at Incheon Hyatt hotel, a sister company of Korean Air and owned by the Hanjin Group.

South Korea’s portal sites and local media have exposed a series of videos and audio recordings of Lee’s emotional outrage provided by her ex-workers, including video captured at a construction site in 2014 where she's caught on camera throwing papers and shoving a female worker. She later denied the multiple public accusations through a statement by Hanjin Group, saying she did not use violence towards hotel employees and denied making the hotel manager kneel.

But she acknowledged “some cases of violence” and “apologized to the victims as well as all others.”

Lee has been summoned by police for questioning next week.

Authorities are also investigating whether the entire family has been engaged in smuggling luxury goods to evade taxes, which includes the head of the Cho family, Cho Yang-ho, chairman of both Korean Air and its parent company Hanjin Group.

In addition, he faces charges of inheritance tax evasion along with his siblings for not properly declaring the value of hundreds of millions of dollars worth of their late father’s property in foreign countries.

Prosecutors raided a dozen of his offices and affiliates simultaneously on Thursday. Cho is expected to be summoned soon after the confiscated materials, including accounting data are analyzed.

ABC News’ Hakyung Kate Lee, Jaesang Lee, and Jiweon Park contributed reporting from Seoul, South Korea.