Police in Shanghai are investigating a female preschool teacher over allegations that she sexually abused a 3-year-old girl with a kidney bean.

Gelin Shuangyang Kindergarten in Yangpu district said it has suspended the suspect, identified only as Lin, 25, until it has seen the results of the inquiry.

That decision followed on a complaint made by the parents of a girl nicknamed Niu Niu.

"When my daughter returned home from school on May 11, she told me, ‘Teacher put a bean in my body’," Qin Lin, Niu Niu's father, said on May 23.

"We didn't believe her at first."

"We asked her teacher the next day, during a spring outing with parents. Lin (the teacher) blushed and turned to look at my daughter. She said there was no way she did that."

He said his daughter was admitted on May 15 to a hospital, where the fingertip-sized bean was removed.

"Niu Niu turned pale when talking about Lin (her teacher) and referred to her as a ‘bad woman’," Qin said.

According to a source with the Kongjiang Lu police station, the girl said she was playing with a few children in the classroom when Lin told her they were going to play a "private game". That is when the alleged abuse occurred.

Qin said he is concerned there is not enough evidence to prove an assault occurred.

"The only reliable evidence was deleted," he said. "The kindergarten told police that the contents of the surveillance camera tape are automatically deleted every four days. Also, my daughter is too young to be a witness."

Gao Pei, an attorney for the Dawn Partners law firm in Shanghai, said the crime of child molestation carries a maximum sentence of five years.

Officials at Gelin Shuangyang Kindergarten apologized to the family last week.

Qin said they begged him not to talk about the incident with the media, saying it was to protect the girl and the teacher, who is planning to get married.

Calls to the kindergarten went unanswered on May 23.

Qin said he and his wife plan to move Niu Niu to another kindergarten soon.