Huugjilt's mother, Shang Aiyun, 62, and his father, Li Sanren, 74, arrives at at Hohhot Intermediate People's Court, Monday.  [Photo from Hohhot Intermediate People's Court’s official Weibo account]

Huugjilt, 19, from the Inner Mongolia autonomous region, was convicted of rape and murder in Hohhot, Inner Mongolia's capital city, in 1996. It took only 61 days from the date of the case to his execution.

The case triggered controversy and resulted in further investigation by judicial officers after Zhao, who was arrested in 2005 on other offenses, confessed to the crimes for which Huugjilt was convicted. Zhao has been in jail since.

However, it took years before the authorities decided in 2014 to retry Huugjilt and Zhao. Huugjilt was declared innocent on Dec 15. His parents received about 2 million yuan in compensation from the Chinese government on Feb 3.

The trial of Zhao began on Jan 5 in the Hohhot Intermediate People's Court.

Zhao allegedly raped and killed 10 women and girls between 1996 and 2005.

Detectives working in the Hohhot public security bureau admitted at the time when Huugjilt was executed that their work performance was rated by an annual quota on how many criminal cases they had solved. They were "eager to wind up a case, and the use of illegal punishment and inducement on suspects existed in case investigations."