Man shot and killed his mother, father and sister then killed himself after family argument in their family house

Homicides and crime rates in the US they are constantly increasing every single day, but what raises the alarm the most among authorities and additionally concerns the communities is that more and more minors are the ones involved in crimes.
This is the main reason why parents in this society strive to show the right path to their kids and the beauties that the life is offering.
But, one minor, whose parents provided everything for him in life, took care for him as best they could, recently committed a crime.
The teenager, for unknown reasons, killed his parents, one of his sisters, severely wounded the other sister, and eventually took his own life.
Law enforcement were dispatched to a report of gunshots heard in an apartment complex after midnight in South Carolina. Officers arrived at the scene and while passing by in the area they heard another shot being fired. The immediately took cover, called for backup and secured the area of the apartment complex.
After a while they entered the apartment and found four people killed and one with serious gunshot wound. The injured person was taken to a hospital for treatment of life-threatening injuries.
The victims were identified as 55-year-old John S., 50-year-old Mary P., 27-year-old Erica S., 19-year-old Johnathan S.
The person who suffered life-threatening injuries was identified as Theresa S., 18.
Detectives started interviewing the neighbors in order to gather more information about the killed family.
One of the interviewed neighbors described them as nice people. “I’ve seen that family walking their dog when I’ve been out with my dogs and my wife has seen them. They’re always really nice,” the neighbor said.
Other neighbor who has been a resident in the apartment complex for five years said he was shocked after hearing about the incident because their neighborhood was very quiet and safe place to live in. He also added that all members of the killed family were very polite. “I’ve seen that family walking their dog when I’ve been out with my dogs and my wife has seen them. They’re always really nice,” the neighbor added.
After gathering evidence, investigators determined the 19-year-old Johnathan was the person responsible for the homicides. He killed his parents, the 55-year-old John S. and the 50-year-old Mary P., his sister, the 27-year-old Erica S., injured his other sister Theresa S., 18, and at the end shot himself in the head.
Further investigation showed that other family member, brother of the shooter, escaped from the house during the incident and remained alive.
Autopsies are scheduled for the shooter and the victims.
The incident is being investigated as a murder-suicide.