Updated at 3.18pm: A woman battered her husband with a dumbbell before cutting off one of his testicles and attacking her son in the early hours of Tuesday morning.
The 26 year-old son heard some noise from his parents' bedroom at about 4am. He was hit on his head by a hard object when he went to check what was going on, police said
He saw his 56 year-old mother, surnamed Leung, stained with blood and his father, surnamed Mak, lying on the floor of their Tsuen Wan flat soaked in blood. He found a blood-stained dumbbell and a knife in the bedroom. He called the police at 4.04am.
The police spokesman said both father and son received head injuries. One of the testicles of the father was cut off.
All three were rushed to Yan Chai Hospital. The son was later discharged and his parents are both in a stable condition.
''The wife was not in a [mentally] stable condition and was not willing to talk about the incident,'' a police spokeswoman said.