Before committing the crime, Tarant published a lengthy statement explaining the objectives and background of his attack.
In the statement, Tarrant describes himself as "an ordinary white man from a normal family, and decided to rise up to ensure the future of his compatriots."
The media said he was attacking Live on Facebook.
Brenton Tarant was born in a low-income working-class family.
He was not interested in studying and after graduating from school he did not go to university and worked for some time to save money later on on travel and tourism. Recently, he has been engaged in "Kebab Removal," a term used on the Internet to symbolize the activity of "preventing Islam from invading Europe".
It was not yet clear whether Tarant was the only executor of the attack, and police said they had arrested four people in connection with the incident.