WASHINGTON (AP) — The slaying of a tourist from Denver in a residential section of northwest Washington may be connected to two subsequent nonfatal attacks on local residents in the same neighborhood, D.C. police said Thursday.

All three victims suffered head trauma and appear to have been “attacked suddenly and without provocation,” Police Chief Cathy Lanier said. There was no apparent motive for the attacks — the victims were not robbed — and no similarity between the victims other than they were walking alone.

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The tourist, 66-year-old Gary Dederichs, was killed Tuesday evening. The other two victims — a 53-year-old man and a
37-year-old woman, both from Washington — were seriously injured and remained hospitalized Thursday, police said.

The man was attacked around 3 a.m. Wednesday, and the woman was struck at 8:40 p.m. Wednesday, police said. Investigators were not sure what sort of weapon was used, but all three were hit on the head with a blunt object. Police initially thought the second victim had been hit by a car.

The attacks occurred within a 10-block radius in the Petworth neighborhood, a mixed-income residential community near the Maryland border. Although a homicide detective told reporters he could not remember the last time a tourist was slain in the nation’s capital, the attacks occurred more than 4 miles from the National Mall and other landmarks, and there was no indication that Dederichs was targeted because he was from out of town.

Dederichs, a retired nurse, was staying with a resident who rented out part of a home using Airbnb.com, a website popular with homeowners who rent space to travelers. Dederichs had used the website previously and described himself on his profile, which was removed Thursday, as “a retired, neat, quiet gentleman.”

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He had lived for decades in a one-story home in quiet neighborhood near the University of Denver campus and worked as a nurse at Swedish Medical Center before retiring. Before becoming a nurse, he had worked in the marketing department at General Motors in Detroit, said Christopher Razzazian, his next-door neighbor and friend.

Dederichs was unmarried and had no children. He took good care of his house and traveled extensively, including taking a recent trip to Turkey, Razzazian said.

“He was an amazing man. He was a little bit quirky,” Razzazian said. “Looking back, you can’t think of anything to find fault with him.”

Dederichs also volunteered with A Little Help, a nonprofit that helps senior citizens continue living at home by offering rides to doctor’s appointments and other services. He gave regular rides to several people, including a woman in her 80s who needed physical therapy, said Paul Ramsey, the group’s executive director.

“She said he was a jewel of a man,” Ramsey said. “He was obviously a guy who spent his life caring for other people.”

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