Interpol has issued an alert for a woman behind an elaborate exam-cheating scam in Singapore which involved phones and headphones taped to students.
Poh Yuan Nie, 57, fronted the racket together with three accomplices, who have all been jailed.
She is thought to have fled Singapore.
Police in the city-state issued an arrest warrant for Poh, also known as Pony, last November. They applied for the Interpol "red notice" the following month and have appealed for information on her whereabouts.
A red notice is a request to law enforcement agencies worldwide to locate and arrest a person pending extradition or similar legal action.
The scam took place across several days in October 2016, during sittings for three tertiary entrance exams.
According to local media, Poh's Zeus Education Centre was engaged to provide tuition to six students - aged 17 to 20 - to help them pass their exams and enter local vocational colleges known as polytechnics.
The students - all Chinese nationals - sat for the papers at different venues while wearing skin-coloured in-ear headphones. Mobile phones and Bluetooth devices were taped to their bodies by Poh and her accomplices, and carefully concealed under their clothes.
Poh's ex-girlfriend Tan Jia Yan, then aged 30, also sat for the papers as a private candidate. She did so with a camera phone attached to her chest via sticky tape, and hidden beneath her clothes.
Using FaceTime, Tan broadcast a livestream of the papers to Poh, her niece Fiona Poh and an employee Feng Riwen, who were waiting at the tuition centre.
The trio then worked out the answers and fed them to the students via their headphones. "If I heard them clearly, I should keep silent, if not, I should cough," testified one student.
The scheme unravelled when an exam supervisor heard unusual transmission sounds coming from one of the students, who came clean when questioned.
One of the students involved testified that he had been pressured by the tutors to cheat, and "did not dare" tell them that he did not want to be part of it.
In 2020, Poh, her niece and Feng were convicted of 27 counts of cheating. They were each jailed for between two and four years.
A judge had called on the trio to testify in their defence, but they chose to remain silent. The prosecution argued that an adverse inference should be drawn from this, including the ultimate inference of guilt.
In 2019, Tan was jailed for three years on the same charges. At her sentencing, District Judge Kenneth Yap said that the sanctity of national exams had to be protected.
"The notion that students can buy [results] by resorting to cheating is offensive. It undermines the principle of meritocracy. It can't be that the rich can procure exam results," he said.
There have been similar high-tech cheating scandals elsewhere. In 2016, medical students in Thailand were caught using embedded cameras and smartwatches with stored information to cheat on their exams.