A prisoner who used a mobile phone to stay in touch with mistresses and defraud them has been sentenced to 13 years and 9 months and fined 220,000 yuan, thepaper.cn reported on Wednesday.

Wang Dong, 28, contacted the women on WeChat using a smartphone given to him by a prison guard at Nehe prison in Heilongjiang province.

Fourteen officials, including the head and political commissar from the prison, were removed from their posts after the scandal was reported by thepaper.cn in January.

Investigators said evidence was insufficient to prove Wang had sex with a policeman's wife while serving another 6-year?sentence and the prison's video record cannot be retrieved.

Some prison officers supplied Wang with mobile phones in exchange for money, investigators confirmed.

According to dbw.cn reports, Wang swindled two women out of more than 110,000 yuan ($17,717) and forced another, a policeman's wife, to visit him at the prison for sex. He contacted the victims through a phone chat platform and blackmailed the policeman's wife using naked videos as threats.

Thepaper.cn reported that Wang sent naked photos of the policeman's wife to her relatives and friends and telephoned her husband. He was reported to prison authorities and the local procuratorate in November.

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