A woman who was wrongfully jailed for about 13 years is seeking state compensation of nearly 10 million yuan ($1.5 million).

Qian Renfeng, 31, and her two lawyers have leveled a complaint against the High People's Court in Yunnan province demanding damages and an apology in major media.

Qian was sentenced to life in prison in 2002 when she was 17 years old for allegedly poisoning children. The sentence was quashed in December because of insufficient evidence.

In February 2002, at a nursery where Qian was working, a toddler died of food poisoning and two other children were hospitalized. Qian, who had prepared the children's meals that day, said she was forced into confessing that she had mixed rat poison in the food.

"The interrogators made me kneel down on the floor for hours and cuffed my hands behind my back," she told media after being released from prison. "In a state of fury, extreme pain and exhaustion, I said I was guilty."

She probably would have spent her entire life in prison if she hadn't been noticed in April 2010 by a group of lawyers who provide free aid to prisoners at No 2 Prison for Women in Yunnan province, where she was an inmate.

Lawyer Yang Zhu, who has provided free legal assistance, found contradictions in her "confession", forged signatures on documents that Qian said she had never seen and an apparent lack of substantial evidence to support her conviction.

In July 2013, the Yunnan provincial procuratorate agreed to reopen the case. Nearly two years later the procuratorate ruled that there was not enough evidence to support the conviction, and advised the provincial court to rehear the case.

According to a white paper on judicial justice and transparency published in June, courts across the nation reheard 1,317 cases and corrected a number of wrongful convictions in 2014.