Beijing police said on Tuesday evening they had not found any evidence that children have been sexually exploited in the RYB Education New World Kindergarten.

Preschoolers at the kindergarten in Chaoyang District were reportedly sexually molested, pierced by needles and given unidentified pills, stirring up a national outrage.

According to police, the investigation showed that a female teacher surnamed Liu, 22, allegedly used sewing needles to "discipline" children who would not sleep. Liu has been detained.

The kindergarten has 78 staff with eight males who have no contact with children in private.

No abnormality was found after the examination of a girl involved in the case upon her parents' request.

Teachers were not allowed to give any drug to children except those presented by parents.

The surveillance footage of the problematic class obtained by police had been damaged, which was found to be due to frequent power outages. Investigation showed that a staff member in the surveillance room was annoyed by the noise of the monitor and frequently cut the electricity after school.

About 113 hours of footage was restored and viewed and no act of abuse was found.

The claims that children have been collectively molested were found to be rumors created by a 31-year-old woman surnamed Liu and a 29-year-old woman surnamed Li. Liu has been detained, and Li received a police warning.

A video clip was broadcast by a TV station on Nov. 23 showing a child saying he was fed pills by teachers. The father admitted that the child has not been fed pills in school, but it was he himself who induced the child to say so.

Parent surnamed Zhao had said that there were naked male "doctors" conducting body checks on her daughter. Zhao admitted that the story was entirely fabricated and she was willing to apologize to the public.

Police said the case is still under investigation.