Nearly a month after a policeman in Linzhou, Henan province, threw down a 7-month-old baby girl to the ground, the top three officials for the city's public security bureau investigating the case have been replaced, people.com.cn reported on Monday.

A group of investigators from the public security bureau in Anyang, a prefecture-level city that presides over Linzhou, have told Linzhou's bureau director, political commissar and deputy secretary of the Party bureau committee to stop their investigation.

The Anyang bureau said it was taking over because the three officials in Linzhou had failed to not only fully investigate the case but had also failed to effectively punish the policeman who allegedly threw the baby to the ground.

The incident happened at about 9 pm on July 20 when a policeman named Guo Zengxi, 50, left a restaurant with three colleagues after having dinner and drinks. Guo, who witnesses said was intoxicated, saw a couple carrying their 7-month-old daughter and made a bet with his colleagues that the baby girl was a toy doll. He then grabbed the baby from her parents and threw the baby to the ground to prove his claim. The baby was seriously injured.

Chinese media exposed the case on Aug 17 and Guo was arrested that same day, nearly a month after the incident. He had been instructed since Aug 4 to take a leave of absence from work but the Anyang public security bureau on Monday said his punishment was insufficient.

The baby was sent to the hospital immediately after the incident and she is now in stable condition.

The investigation by the Anyang team is ongoing.