MOUNT KISCO, N.Y. -- It was the kind of life and death that might have slipped by without much notice. Rene Perez was homeless, a drinking man from Guatemala, an occasional laborer in this affluent community, and he was found unconscious on a desolate road in a nearby town only to die soon afterward.

But the county medical examiner ruled his death in the early hours of April 29 a homicide, probably from blows to the abdomen, and soon police from Bedford, where Perez was found, said that three Mount Kisco officers were being investigated in connection with his death. The officers -- who had responded to a 911 call from Perez and left him just 44 minutes before he was found unconscious -- were put on desk duty, their patrol cars temporarily impounded.

Perez's killing has exposed tensions between well-off white employers and poor immigrant workers in this northern Westchester County town of 12,000 about 40 miles north of New York, where 75 percent of residents are non-Hispanic whites and about 25 percent are Hispanic.

"People here are afraid to talk to the police," said Fernando Mateo, president of Hispanics Across America, an advocacy group, at a vigil here he organized Wednesday night. About 100 people, mostly Latinos, stood in the rain outside the red brick Village Hall carrying signs with slogans such as "We Have the Right to Live," and "No One is Outside the Law."