BUSAN (Yonhap) -- A 15-year-old boy allegedly killed his mother after being scolded for excessive computer game playing, then took his own life at his home in the southern port city of Busan, police said Tuesday.

   The 43-year-old mother, identified only by her surname Kim, was found dead in her bedroom by her 12-year-daughter at around 7 a.m.

Tuesday, police officials said, adding the son, a middle school junior, was also found hanging from a gas pipeline in an apparent suicide.

   The girl reported to police that her mother and brother often had fights over his gaming addiction and they quarreled severely late Monday night. She said, "I thought they were fighting like they normally do and just went to sleep. When I woke up in the morning, my mother was lying dead on the bed."

   Police officials discovered a note the son left to his maternal grandmother, who was living next door, which said, "I was scolded for game playing and did what I shouldn't have done to my mother. I am sorry."

   The police suspect that he committed suicide after feeling guilty for killing his mother and said they are looking into the exact cause of the incident.