Wang Wenxian, a farmer from Dangshan county, Anhui province, his brother Wang Wenli and an accomplice Fu Xiaokui, were found to have offered students from two universities in Hefei, capital of Anhui, 1,000 yuan each to take the exam, according to Su Wei, a policeman with the Dangshan Public Security Bureau.

Students told police that the organizers had promised to pay each student who passed the exam 10,000 yuan in order to sell on their exam certificates to students who had failed to achieve high enough grades to be admitted into university for 15,000 to 20,000 yuan.

The three men gave Sun Feng, a senior student from Anhui University, who has also been arrested, more than 300,000 yuan (39,400 U.S. dollars) for him to recruit students and bring them to Dangshan county to sit the exam, police said.

Police added that the majority of the students, who had agreed to the plan, did not travel to Dangshan to attend the exam as they had heard the police had been alerted to the scam.

Six students, five from China Science and Technology University and one from Anhui University, were caught by police in Dangshan a day before the exam took place on June 7 and 8.

It appears the scam organizers colluded with someone inside the education system in Dangshan in order to provide the university students with fake IDs so they could sit the exam with the final-year senior high school pupils.

A report by China Youth Daily newspaper said that a teacher suspected of helping the students obtain fake exam registration certificates had been arrested.

However, the local PSB official Su Wei told Xinhua on Thursday that no teacher had been arrested so far, but some local teachers were being questioned by the police.

Jiang Liancai, director of the Dangshan Education Bureau, said a total of 12,445 people in the county were registered to attend the exam, but as many as 703 of them did not attend, an absence rate of 5.6 percent, which was double the average rate of 2.7 percent in previous years.

"Some of the absences may be related to the scam," Jiang said, adding that local authorities were doing a checkup of the 703 absent candidates one by one and would announce the results as soon as possible.

Police are still hunting for two other people suspected of being involved in the scam.

The authorities of the two universities in Hefei have yet to punish the students who initially agreed to take the exam.

Competition for university places is fierce. Around 9.5 million students in China sat the annual exam on June 7 and 8 this year to compete for 5.67 million university places.

In northeast Jilin province, police arrested three people who were caught using wireless microphones to provide answers to students attending the exam and a cheating scam in central Henan province led to the sackings of the principal and deputy principal of a middle school and a deputy principal of another middle school.