The 30-year-old lawyer suspected of killing prominent Orono physician Dr. Stephen Larson had expressed hostility toward Larson because of how he believed the doctor had treated his mother in an undisclosed medical situation, police said Monday.

Ted C. Hoffstrom of St. Anthony, confronted Orono police outside the 74-year-old OB-GYN doctor's home with a semiautomatic handgun Friday night. "Diligent attempts to negotiate" with Hoffstrom failed and he was shot and killed, authorities said. Larson was then found dead inside the house, shot with the gun Hoffstrom had wielded, ballistics tests would show.

"This is a tragedy of epic proportions for both families involved, as well as the community of Orono," Hennepin County Sheriff Rich Stanek said Monday afternoon at a news conference in Minneapolis.

Hoffstrom's family members either did not answer calls or declined to comment Monday. And Larson's son, Christopher Larson, reiterated Monday that his family did not want to comment.

Just before 9 p.m. Friday, Orono officers responded to a call about trouble at Larson's house on Heritage Lane. Larson had been on the phone with someone who heard him answer the door and heard startling noises. When Larson didn't return to the phone, the person he had been talking to called police, Stanek said.

"We know who committed this murder, yet many unanswered questions remain," Stanek said.

The four Orono officers involved in the shooting were Police Chief Correy Farniok, Officer Brad Schoenherr, Officer Paul Hooper and Officer Joshua Neham, authorities said. They remain on paid leave.

"Orono is a safe community, and there is no threat to the public at this time," Deputy Chief Chris Fischer said.

Records going back to 2010 show no police calls to the Larson residence, a Hennepin County spokeswoman said. St. Anthony police said they've been called twice to the home where Ted Hoffstrom and his parents lived, including on Friday, both times to check on welfare. Further information on such checks is private, they said.

An outpouring of sorrow

Larson, who founded a medical group in Edina and Burnsville, was a well-known expert on pelvic surgery and a former adjunct professor in the Department of Obstetrics, Gynecology & Women's Health at the University of Minnesota Medical School.

State records show that Larson was reprimanded in unrelated instances twice in his 40-year career as a licensed physician, in 1990 and 1996. He was fined $1,000 in each case, and no corrective action was required. According to state birth records, Larson was not the primary doctor at Hoffstrom's delivery in 1983.

Sandy Kamin, administrator at Larson's private practice clinics, worked with him for 25 years. She said Larson was a man who loved his job and his patients and set the bar high for his colleagues.

Kamin said clinic staffers gathered for about 90 minutes Monday morning to tell stories about Larson and share their feelings about his death.

"He's our mentor," she said. "He was the person we all looked to so we could be better at our jobs."

Kamin said that even though Larson founded the clinic, he treated his partners as equals and made all of his employees feel respected.

The clinics in Edina and Burnsville had a steady stream of patients and well-wishers stopping by on Monday. "Today has been amazing," Kamin said. "Our patients were bringing in flowers and baked goods and cards and really sharing their sympathy with us."

Kamin said she has also received dozens of calls and notes from other physicians who knew Larson during his long career in the area.

"He really was a pillar in the community," she said.

'Doesn't make any sense'

For some who knew Hoffstrom, his death and suspected involvement in Larson's death came as a complete shock.

Hoffstrom graduated from the University of St. Thomas law school in 2009 and was sworn in to the bar last month. An online résumé listed brief stints as an intern for state Sen. Chuck Wiger in 2006 and for two Hennepin County District Court judges in 2008. He also spent his summers for 12 years working at Gross Golf Club in Minneapolis.

He had a virtually spotless record, and a friendly demeanor, friends say.

"He was one of the best guys I've ever known," said Nick Houwman, a high school friend who had seen Hoffstrom three weeks ago after he was sworn in to the bar on Oct. 25. "This doesn't make any sense."

Another friend, Chris Miller, stayed in touch with Hoffstrom after they studied journalism at the University of Minnesota.

"That's not the Ted Hoffstrom I know," he said of the shooting. "It's shocking."

At Hoffstrom's home, family members posted a statement on the front door Sunday night expressing sympathy for the Larson family, and adding that "many questions remain unanswered."

"Our hearts are broken for all of those affected by this tragic event," the note said. "We are shocked and saddened by this news."

Work-related violence is not unknown to the nation's doctors. An average of five physicians and 20 health care providers die each year in the United States as a result of assaults or other workplace violence, according to U.S. Bureau of Labor Statistics reports dating back to 2003.

That tally, however, does not include killings outside the workplace and would not have counted Larson's death.