A former vice president of South Korea's top airline, Korea Air Lines Co., was indicted Wednesday on charges of obstructing aviation safety after she ordered a crew member to deplane over in-flight service last month.

Announcing the interim outcome of their one-month probe, investigators at the Seoul Western District Prosecutors' Office said they have charged Cho Hyun-ah, the eldest daughter of Korean Air chairman Cho Yang-ho, with violating the nation's aviation safety law and criminal code.

The charges against Cho include violations of aviation safety regulations -- changing flight plans and assault on a plane -- and coercion and interference in the execution of duty, according to the prosecutors.

Cho resigned as a vice president of cabin service four days after a national uproar over her conduct aboard a Seoul-bound Korean Air flight from New York on Dec. 5.

The plane had already been taxiing when she ordered the chief flight attendant to deplane over the way she was served macadamia nuts -- in an unopened pack instead of on a plate. She was angry because she believed the crew did not follow the proper procedure for serving nuts to first-class passengers.

The flight was subsequently returned to the gate to deplane the purser, causing an 11-minute delay in its arrival at Seoul's main gateway, Incheon International Airport. More than 250 passengers were on board.

The prosecution office said it had additionally brought charges of interfering in the execution of a government official's duty as she had allegedly exerted influence in the government investigation.

Cho systemically interfered with the investigation carried out by the Ministry of Land, Infrastructure and Transport following the incident, prosecutors alleged.

"Cho systemically interfered with the investigation by the government agency and prompted an insufficient investigation," said Kim Chang-hee, a prosecutor probing the case.

Cho had already been detained since Dec. 30 after a local court issued a warrant, citing "the gravity of the issue as well as the organized efforts to cover up her involvement from the initial stage."

A Korean Air executive, identified only by his surname Yeo, was also indicted on charges of ordering employees to delete an initial report of the incident, prosecutors said.

A transportation ministry official, surnamed Kim, who leaked details of a government investigation into the case involving Yeo, will also be indicted, they added.

Prosecutors said they will also continue looking into suspicions that government officials got free upgrades from Korean Air.

Allegations recently surfaced that several ranking transportation ministry officials were bumped up to business class regularly for free. (Yonhap)