Police say the 9-year-old sister of 7-year-old Zeus Diviaio shot him inside a bedroom, leaving him with a wound to the upper chest. The boy was pronounced dead after being taken to the hospital.
It happened at 1502 Green Mountain Drive just after 4:30.
According to the police report, the 9-year-old, who was described by her father as having "high functioning autism," told her dad that two men had come into the apartment and shot her brother.
The father told officers his daughter often told stories and that the apartment door had been locked when he and his wife left only for a few minutes. The man and his wife had left the children alone while they signed paperwork at the apartment office, the report said. The couple opened the door with a key upon their return.
Blood was found in a back bedroom where the father told officers he kept guns inside a case and more blood was found in another bedroom where the boy was lying when police arrived, according to the report. Two handguns were found inside the case.
The parents found the boy shot after their daughter told them he had been hurt while they were out.
Police said there was no evidence of forced entry to the apartment and nothing was missing.
The case has been sent to the prosecutor's office, who will determine if any charges will be filed.