A Minnesota family says they have been “torn apart” after a 16-year-old boy was fatally stabbed by his 12-year-old brother at home.

Sebastian Harris was a junior at Hopkins High School, where the principal informed students and parents of the teen’s death.

Principal Doug Bullinger said he has spoken with Harris’ family after the "tragic event that has torn a family apart,” reported The Star Tribune.

The fatal incident occurred on Saturday night at Harris’ home following an altercation.  According to charges filed in Hennepin County juvenile court, Harris was stabbed in the chest by his brother with a kitchen knife.

Details surround the suspect and charges have not been revealed due to his young age.

The Medical Examiner's Office said Sebastian died of sharp-force injuries as the result of a homicide.

"We know there was some sort of an altercation between the two boys," Minnetonka Police Chief Scott Boerboom said at a news conference Sunday.

"The mother and other family members were home at the time of the incident," a police statement read. "Police are working with the family to determine the circumstances that led to the stabbing."

Although the 12-year-old suspect was not injured, he was taken to a hospital for evaluation and was then detained.

In an online fundraising campaign, Harris was described as a vibrant young man who helped others.

"Sebastian always stood up for the underdog and did what he thought was right," the organizer of a support fundraiser wrote online. "He had a contagious sense of humor and an incredible imagination."

A fellow karate athlete said on Facebook that "Sebastian was a beautiful part of our Karate family. He looked after the boys, helped keep them on course, and was always smiling."