Charges have been filed against an off-duty Illinois State Police trooper suspected of shooting a woman to death, then turning the gun on himself in a domestic attack in Westchester early this morning, authorities said.



Brian Himber, 31, of the 4100 block of North Central Avenue on Chicago's Northwest Side, was charged with two counts of first-degree murder for fatally shooting 29-year-old Tracy Mays, age 29, according to a statement released by police Sunday night.



Police could not immediately say why two counts of murder were approved.



Himber remains in the custody of Westchester Police with a self-inflicted gunshot wound, according to the statement.



Mays was fatally shot at a home in the 10900 block of Nelson Street in the west suburb and was declared dead a little after 1 a.m. at Loyola University Medical Center in Maywood, according to the Cook County medical examiner's office.



The medical examiner's office found following an autopsy that the victim died from multiple gunshot wounds in a homicide. Police did not release information on her hometown.



After shooting Mays, Himber tried to kill himself, police said. The man and woman had been attending a graduation party at the home, Westchester police said in a news release. Police were called to the home at 12:23 a.m., according to the release.



Himber was in critical condition at Loyola with at least one self-inflicted gunshot wound, authorities said.



The man involved in the apparently domestic-related shooting was an off-duty Illinois state trooper, state police spokeswoman Monique Bond said in an email. Himber, hired in 2004, has been relieved of his police powers, according to Bond.



The trooper is not believed to have used his service weapon in the shooting, authorities said.



Neighbors said the party was raucous but nothing unusual.



Kathy Syregelas, 32, said the family was celebrating the eighth-grade graduation of one of their children and threw a backyard party. The music was loud, but Syregelas said it appeared to be a normal summertime get-together.



"I heard kids screaming at one point late last night but didn't think anything of it," Syregelas said.



Tribune reporters Liam Ford and Rosemary R. Sobol contributed



chicagobreaking@tribune.com



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