A 24-year-old man posed as a woman on Facebook and took semi-nude photographs of a girl he befriended.
Nanyang Siang Pau reported that Song Jian Sheng, a Singaporean, befriended the 16-year-old girl in June 2011 and then chatted with her with a web camera.
However, Song claimed that his web camera was not functioning.
He then suggested they play a game of Hangman with the rule that the person who lost would remove a piece of clothing.
The teenager agreed, and after losing a few rounds, she was left with only her panties on.
Song then asked her to pose for him, which she did. Unknown to her, Song took several screenshots of her.
Five months later, Song tried to chat with the girl again but she declined.
He then threatened to upload her semi-nude photos online.
Fearing for her reputation, the girl had to undress herself again in front of the web camera.
Song was subsequently arrested.
He was sentenced on Thursday to four weeks' jail for threatening to post those pictures online.