Hong Kong Police murder
Police in Hong Kong arrested a 34-year-old man over the murder of a 15-year-old girl. Lam Yik Fei/Getty Images

Hong Kong was shocked by another brutal murder related to the city's underground sex industry, as the half-naked body of a 15-year-old girl was discovered bound and gagged at a local dump - just weeks after a British banker was charged with the killing of two escorts.

Police said the victim, Kwok Wai-ming, from the Tsing Yi island district, had hands and legs bound together with plastic strips and adhesive tape and might have died during a sex game.

"Her head, neck and four limbs were bound with plastic strips and adhesive tape," said Superintendent Lam Shu-wing of Kowloon West regional crime unit, the South China Morning Post (SCMP) reported.

Detectives said the girl was involved in compensated dating - a form of prostitution - and also posed for nude pictures for money.

Her body was discovered stuffed in multiple layers of plastic and nylon bags by a worker at a Mong Kok waste collection centre.

The cleaner, Chan Lai-kuen, 58, said she became suspicious after helping a "polite" man loading the heavy bag into a bin.

"He claimed it was just usual rubbish," Chan told SCMP. After the man left she opened the bag to find the body naked from the waist down. "I just saw hair and plastic strips inside the bag," she added.

Police have arrested a 34-year-old former clerical worker after analysing security camera footage from buildings in the area.

Motives of the killing and the cause of death are not yet clear. An autopsy has been ordered.

According to an early police reconstruction, the killer got in touch with the girl through an online dating forum.

He invited her to his flat where it is thought she was knocked unconscious by a blow to the head, possibly with a glass bottle. It is thought the assailant then stuffed the girl into a suitcase and took it to a hotel close to the garbage collection centre, where he spent the night.

The next morning he dumped the body. Police said that an initial analysis of the body revealed the victim recently had had sexual intercourse.

The killing comes after a British banker was arrested for the murders of two sex workers, Jesse Lorena and Sumarti Ningsih, whose decomposing bodies were discovered in his Hong Kong flat.

Rurik Jutting, 29-year-old Cambridge University graduate who described himself as an "insane psychopath" is due to stand trial in July after he was ruled mentally fit.