BEIJING (Reuters) - China’s top prosecutor will review a controversial sentence in which a man was jailed for life after killing a loan shark who had sexually assaulted his mother, in a case that has again ignited public anger over police incompetence.

The government has promised to redress miscarriages of justice after several high profile cases, including wrongful executions of people later proven to be not guilty.

Yu Huan, from Liaocheng in the eastern province of Shandong, was sentenced to life in jail in February after he used a knife to attack four of his mother’s creditors who exposed themselves to his mother while demanding a debt be repaid last April, according to state media. One of the creditors died.

Yu’s mother Su Yinxia borrowed more than 1 million yuan ($145,342.50) in 2014 and 2015 and verbally agreed to 10 percent monthly interest, the state-run Global Times said, citing an initial court verdict.

When four of the loan sharks went to the office to demand repayment, police were called but left without arresting anyone, the report added. After the police left, the dispute escalated leading to the death, it said.

Yu’s attorney, Yin Liqing, filed an appeal last month against the sentence and will also sue police for failing to carry out their duties, which Yin says resulted in the killing, the paper added.

On Sunday, the country’s top prosecutor said it will examine and review the evidence to find out if Yu was acting in self-defense, and investigate possible dereliction of duty by the police. Shandong’s high court also announced on Sunday it has accepted Yu’s appeal.

Liaocheng police declined to comment when reached by telephone.

The case has been widely discussed on Chinese social media, and is the number two trending topic on Weibo, China’s answer to Twitter, with many people saying a life sentence was not justified and criticizing police inaction.