Twenty-nine people suspected of providing fake registration information for students taking the high school entrance exam in Xi'an, Shaanxi province, in June have been arrested, and 11 have been criminally detained.

In a notice issued on Sunday, the city police said a local tutoring school fabricated a government stamp to provide fake registration information so that ineligible students from other provincial regions could take the exam in Xi'an. Police arrested six people and detained five who work at the school.

Also, in two separate notices issued on Saturday, police said they arrested 23 people and criminally detained six who work at another tutoring school and an education institution on suspicion of their involvement in a similar crime.

The students are referred to as "returnee students". They have household registration, or hukou, in Xi'an, but study in other cities and returned to Xi'an to take the exam. There are two main paths for "returnee students".

First, children of migrants from Xi'an who study in the city where their parents work, but return to Xi'an to take the senior high school entrance examination, are considered "returnee students". Second, Xi'an uses preferential policies to attract talent and allow them to obtain Xi'an household registration. Their children also meet the criteria for being called "returnee students".

Xi'an education authorities said that this year, 3,608 students sat the high school entrance exam as "returnee students", accounting for 3.5 percent of all test takers.

The incident has prompted a heated debate on social media platforms about fairness in education.

Some argued that the students cheated by fabricating their registration information to gain access to the exam. Others said the students are from more populous regions and face much fiercer competition in enrollment tests, and that the bigger problem is the uneven distribution of educational resources in provincial regions.

It is not uncommon for students in a populous provincial region to go to another region to take the high school or college entrance exams to avoid the intense competition.

In China, university enrollment is based on students' rankings by provincial regions, not nationally.

The Ministry of Education has asked schools nationwide to crack down on "gaokao (college entrance exam) migrants".

The local government in Xi'an said that it has set up a joint investigation team to examine household registrations, school registrations and the examination results of the 3,608"returnee students" this year.

Students who are found to have falsified information as a means to obtain registrations to senior high school exams will have their enrollment qualifications canceled, the local government said in a notice released early Saturday morning.

It will also crack down on educational institutions and people who cheat to get registration slots for students.