ZHENGZHOU, June 18-- A police investigation into cheating during this month's national college exam has been launched in central China.

On Wednesday, police in Henan Province said they were interrogating the parents of two college students and investigating teachers. Police are also investigating in Hubei Province, as students from there were reportedly paid to sit the exam, known as gaokao, on behalf of others in Henan.

The scandal, exposed by an investigative program on China Central Television on Tuesday, sparked fresh concerns about flaws in the exam, which involved more than nine million students on June 7 and 8.

Cheating scandals are a common occurrence each year in China.

Five people believed to be college students were paid by organizers to sit the exam, according to the report. The organizers claimed everything would be okay even if the substitute students were caught.

They sat the exam in Qixian and Tongxu counties in Henan, where fingerprint recognition was used prior to entering classrooms. The organizers provided fingerprint films of the real students for the substitute examinees.

Despite measures to prevent cheating, this latest scandal has sparked fresh concerns about flaws in the system and corruption.

"I was very surprised at the CCTV report. I did not think someone could cheat under such strict measures," said Bai Shiping, principal of Qixian County No.2 High School, an exam venue where the cheating took place.

"The cheating has a very bad impact. We strongly oppose this as it will affect both the fairness and justness of gaokao students, as well as the teaching and learning environment," said Bai.

Gaokao is seen as the most important opportunity for students to change their fate. Some poor performing students take risks and turn to cheating.

"High-tech means, such as fingerprint machines, are increasingly used before sitting the exam but if people turn a blind eye to them, then what is their use?" questioned Bai. "The key is staff administration. The chain of cheating has corruption behind it."

Prior to this year's gaokao, police in Jilin, Jiangsu, Shandong and Hubei provinces busted a number of gangs accused of organizing methods to cheat, such as manufacturing and selling wireless devices, said the Ministry of Education.

Last Thursday, a township government official surnamed Zhang and his brother-in-law in Liaoning Province were given suspended jail terms of 18 months and one year respectively for illegally obtaining state secrets. Zhang sold electronic devices to students during gaokao last year.

According to an education regulation, students who cheat will be stripped of their enrollment qualification for a period ranging from one to three years. College students who sit college entrance exams for others will be expelled from universities or colleges.

To prevent cheating, punishments must be more severe and rules for gaokao must be stricter so there is no opportunity to cheat, said Bai.

Chu Zhaohui, a researcher with the National Institute of Education Sciences, called for reforms in the college recruitment system and the introduction of professional organizations to run exams.

"Education equality is a start. If there is no equality in education, how can we expect equality in other fields?" asked Ye Xiaojian, a politics teacher at Qixian County high school.