BROOKLYN, New York -- A 15-year-old girl has been charged as an adult for allegedly killing her mother and her mother's boyfriend in their Brooklyn apartment.Destiny Garcia was charged with two counts of second-degree murder and two counts of criminal possession of a weapon. Detectives said she confessed to the murders during questioning.Police identified the victims Monday as 38-year-old Rosie Sanchez and her boyfriend 40-year-old Anderson Nunez.The two were found inside their apartment on Batchelder Street in the Sheepshead Bay Houses. Police said their bodies had been been in the apartment since Dec. 27, and that Garcia lived in the apartment with them.According to the New York Police Department, Sanchez was shot multiple times in the chest and found sitting in a chair, and Nunez had been both shot and stabbed. He was found on the living room floor. Both were pronounced dead at the scene.While talking with detectives, police said Garcia told them her mother had been physically abusive to her on at least one occasion."We don't believe this is at all, initially, an act of self defense. She went and got a gun from another individual that we're trying to find right now, to commit the homicide," said NYPD Chief of Detectives Robert Boyce.Police said that person is a 15-year-old boy. Officers described the scene as "bloody," and hard to process.While the bodies were in the apartment, Garcia went to Times Square to ring in the New Year with a friend, police said.