Two incidents in Beijing and Shanghai involving teachers sexually assaulting students when giving private tutoring have attracted wide public attention and raised concerns among parents about children's safety.

A junior middle school teacher in Beijing was detained in Haidian district on suspicion of sexually assaulting a 17-year-old female student, the Mirror, a newspaper in Beijing, reported on Friday.

The teacher, surnamed Zou, used to teach the student math at school and the student's father, surnamed Wang, hired Zou in September 2015 to privately tutor her after school.

According to the student, she was assaulted in April last year for the first time, and then on three other occasions in July, August and December. Zou allegedly intimidated the student to prevent her from telling anyone about the incidents.

On Dec 25, Zou was caught sexually assaulting the student on a surveillance camera that Wang had installed upon his daughter's request.

Wang said Zou charged him 700 yuan ($102) per hour for the tutoring, and he had paid Zou more than 160,000 yuan over the past 14 months.

"If I didn't see it myself, I wouldn't have believed that a teacher from a well-known school in Haidian district could have done this," Wang was quoted as saying by the Mirror.

In a similar incident in Shanghai, a teacher at a private junior middle school, surnamed Qian, was recently sent to prison for two and a half years for sexually assaulting and intimidating a female junior school student when he gave the student tutoring at his own house.

He was also banned from working in the education field for at least three years after he is discharged.

Some netizens described the actions of the two teachers as "unbearable" and "unforgivable".

To regulate teachers' actions and protect students, the Ministry of Education released a series of guidelines in October 2014, stipulating that teachers found to have sexually harassed a student or had an "improper relationship" with a student will receive warnings, be degraded, fired or transferred to judicial departments.

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