Now to the growing murder mystery many minnesota. A prominent physician gunned down in his home. The apparent shooter also dead, killed by the police on the scene. John muller has the story. Reporter:... See More
Now to the growing murder mystery many minnesota. A prominent physician gunned down in his home. The apparent shooter also dead, killed by the police on the scene. John muller has the story. Reporter: This morning, a twisted crime that may have been borne 30 years ago. Dramatic moments as police responded to a call of an armed man outside the home of the prominent dr. Steven larson. Things escalated quickly and turned deadly. We need the tase them asap here. Shots fired. Start balance. Reporter: The unidentified man shot dead. Inside the home, the body of the 74-year-old doctor, also shot dead. His wife out of town. We've got one more down in the house. Reporter: This morning, the medical examiner's office releasing reports. Cause of death for hoffstrom and larson, gunshot wounds. A source with knowledge of the case telling our affiliate that dr. Larson actually assisted in hoffstrom's delivery 30 years ago. There is no way anyone swrould had ill will to him. Reporter: He delivered thousands of babies over his 33 years of practice, winning awards and international acclaim. Colleagues say the four and grandfather was nearing retirement. It was devastating because, you know, his job, his work, it was his passion. Now that choice is taken out of his hands. Reporter: Sunday, hoffstrom's family posted a note on their door. Our heart felt prayers and sympathy to the family of dr. Steven larson. We're shocked and saddened by this news. Neighbors and former classmates describe ho if rks fstrom as a likable guy, someone they would never think would do something like that. We could get a motive later today. We'll see what happens.
This transcript has been automatically generated and may not be 100% accurate.