Real estate agent Mary Macaluso says she had an appointment to meet a family about the sale of a home in the Long Island hamlet of Syosset on Sunday—but when she got there, they were all dead. Police say 59-year-old Joseph DeLucia, upset over his mother's death and the possibility he would be forced to leave the home he had shared with her, killed his three siblings and a niece before "shouting incoherently" and killing himself on the home's front lawn, reports. His mother, 95-year-old Theresa DeLucia, died last Monday.

Her funeral was on Friday, two days before the murder-suicide. "The gunman's perception was that he was being cut out of the will and that he would be displaced with nowhere to go," Nassau County Police Detective Capt. Stephen Fitzpatrick told reporters on Monday.

He said that in one of most horrific scenes he has ever seen, DeLucia killed his relatives with 12 blasts from a shotgun in a rear room of the home. The victims were identified as siblings Joanne Kearns, 69; Frank DeLucia, 71; Tina Hammond, 64; and Hammond's 30-year-old daughter, Victoria Hammond. Fitzpatrick said that DeLucia, a mechanic, had hoarding tendencies and that the house was full of tools.

Macaluso tells that one of the siblings had asked them to "meet with them to give an idea of what they should do with the house before they list it" while two siblings who had traveled from out of state for the funeral were in town. Fitzpatrick said that according to surviving relatives, DeLucia wasn't.