SINGAPORE - A construction worker had unprotected sex with a girl half his age whom he had met online, even doing the deed on her parents' bed.

Dong Yongwei, 24, was first invited home by the 12-year-old primary school student just three months after befriending her on chat service WeChat.

On Thursday, Dong, a Chinese national, was sentenced to a year in prison after admitting to two counts of sex with the minor, committed on Sept 20 and Oct 4.

The court heard that the pair had exchanged mobile numbers and communicated through messages and calls in Mandarin, after meeting in June on WeChat. They first met in person later that month.

On Oct 4, Dong visited the girl at her HDB flat in the north when her mother was not at home. After some hugging and kissing, Dong suggested that they have sex but she was reluctant as she was afraid of getting pregnant. But she agreed after he convinced her.

After having sex, they went to the market together. They returned to the flat with groceries and she began cooking for her mother.

The police were called after her mother returned and discovered what had happened.

Deputy Public Prosecutor Carene Poh pointed out the big age gap between Dong and his victim, adding she was barely pubescent at the time. There had also been a risk of an unwanted pregnancy as they had indulged in unprotected sex.

Dong came to work in Singapore last December. He pleaded guilty to one of the two offences, with the other taken into consideration. He could have been jailed for up to 10 years and fined.