Hong Kong police are hunting for two masked burglars who broke into a villa in Sai Kung and threatened the residents with a knife before fleeing with HK$30,000-worth (US$3,839) of valuables on Thursday.

At 4am, two burglars, who spoke with mainland accents and carried a knife, broke into a residence at Green Peak Villa on Pak Kong Au Road, news website HK01.com reported.

Four people, including a couple aged around 50, their 20-year-old son and a domestic worker, were asleep in the house at the time.

The couple were wakened by the sound of breaking glass and discovered two men in their bedroom, one of them brandishing a knife.

They ransacked the bedroom and took away HK$12,000 in cash, four mobile phones, one iPad and three watches. The total value of items stolen was around HK$30,000, Oriental Daily reported.

The duo then left the house through the kitchen door and disappeared on a hillside covered with vegetation.

Police received a report and sent officers to search for the intruders, but they were unable to find them.

Police believe that the burglars gained entry to the house by breaking a window in the kitchen door.

Officers from Wong Tai Sin Police Station are investigating the case.