(CNN) -- A former hospital worker systematically shot and killed four people in upstate New York on Saturday, authorities in two counties said. Former hospital worker Frank Garcia, 34, has been accused in the shooting rampage. Frank Garcia, 34, was arrested Saturday afternoon. Garcia knew all four victims, police said, but they didn't reveal details about the relationships. "The individuals who were shot were known to the suspect. It was not necessarily a random act," Monroe County Sheriff Patrick O'Flynn said. The first two victims -- Mary Sillman, 23, and Randall Norman, 41 -- were fatally shot before 5 a.m. at Lakeside Memorial Hospital in Brockport, where Garcia was once employed, O'Flynn said. Another woman was wounded and is undergoing treatment at a nearby hospital, he said.
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Suspect went door-to-door in search of victims' residence, authorities say
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Christopher Glatz, 45, and wife Kim, 38, were shot "execution-style" in home
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The couple's teenage children at suburban Rochester home but were not injured
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Mary Sillman, 23, and Randall Norman, 41, shot at a hospital earlier Saturday
Garcia was to be arraigned Saturday night in @placeholder, where the first shootings occurred, on two counts of first-degree murder and one count of attempted murder in the second degree, O'Flynn said.