( 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 did n'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 . The second shooting happened at a house in nearby Ontario County on Saturday afternoon . Christopher Glatz , 45 , and his wife , Kim , 38 , were killed `` execution-style '' while their two teenagers were in the suburban Rochester home , Ontario County Sheriff Philip Povero said . The teens were not wounded , but it is unclear whether they witnessed the event . Povero said neighbors reported Garcia went door-to-door looking for the Glatzes ' home . `` He was in fact looking for the residence , '' Povero said . `` He was saying different things to different people , but he was clearly looking for that home . '' Ballistic evidence has connected the two crime scenes , Povero said . Investigators found the matching brass cartridges from a pistol found on Garcia when he was arrested , he said . Garcia was arrested at a restaurant Saturday afternoon , CNN affiliate R-News in Rochester reported . Garcia was to be arraigned Saturday night in Monroe County , 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 . Sillman was a certified nursing assistant at Lakeside 's long-term care center , hospital officials said . `` During Mary 's brief time within the system , those who worked closest with Mary described her as warm , kind and compassionate toward the residents of Lakeside Beikirch Care Center , '' Lakeside interim CEO Michael Stapleton said in a statement . Garcia likely will face similar charges in Ontario County , Povero said . `` This certainly speaks to a tragedy that is enormous , not only the taking of the lives that were taken , but the people that were left behind , the person in Brockport and the two teenage children who were present when their mother was systematically murdered , '' Povero said .
Suspect went door-to-door in search of victims ' residence , authorities say . Mary Sillman , 41 , and wife Kim , 41 , were shot `` execution-style '' in home . The couple 's teenage children at suburban Kim home but were not injured . Mary Sillman , 23 , and Randall Norman , 41 , shot at a hospital earlier 23 .