Police believe the man, 32, is linked to the death of a woman found dead on Monday in an apartment in a residential district on Hong Kong island, police spokeswoman Michelle Lau said.

The man has not been charged with any crime.

Police earlier said the woman, 27, was found unconscious inside the apartment's bathroom with her forehead swollen and lower jaw injured. Post-mortem examination showed she had died of suffocation, Lau added.

The woman was the fourth sex worker killed in Hong Kong since Saturday.

The bodies of three other sex workers, ages 30 to 35, were found in apartments in the suburban New Territories. One was strangled with a shower hose, and the apartment where she was found had been robbed, police said.

An unemployed Pakistani man, 24, was arrested and appeared in court Wednesday to face charges of murdering those three women. The suspect faces life imprisonment if convicted. -- AFP