WASHINGTON — D.C. police say the slaying of a tourist in a residential section of northwest Washington may be connected to two nonfatal attacks in the following 27 hours in the same neighborhood.

Police Chief Cathy Lanier said Thursday that all three victims suffered head trauma and appear to have been attacked suddenly and without provocation. Lanier says there's no apparent motive for the attacks and no similarity between the victims other than they were walking alone.

The tourist, 66-year-old Gary Dederichs of Denver, was killed Tuesday night. The other two victims were a 53-year-old man and a 37-year-old woman. They were seriously injured and remain hospitalized. The attacks occurred within a 10-block radius. Police say there isn't any evidence Dederichs was targeted because he was a tourist.