Bobby Vanderhall, 34, was accused of breaking into his mother Lynn Reichenbach-Vanderhall's house and through the basement door and beating his mom before doing the same to his sister, Melissa Vanderhall and her friend Janel Simpson, one of the women visiting the house.
Suffolk County police say Vanderhall had a history of emotional problems, and his mother had gotten a protective order against him and had thrown him out of their Hempstead home.
Bobby Vanderhall was arrested nearby, sleeping in a auto.
Police said Vanderhall then found his mother in the living room and started to bludgeon her with the hammer. Bobby Vanderhall stayed in the house for a short time before fleeing, and was apprehended within a two-mile radius of the scene sleeping in a auto, said Nassau County Det.
Police later found Vanderhall sleeping inside a parked auto just two miles away from the home and arrested him. "The most attractive memory of my daughter was her smile, her love, she was so protective of me", said Wendy Simpson, the mother of one of the victims. Another family friend fought off the suspect in the midst of the chaos and ran into the street to beg for help.
The fourth woman was later taken to the hospital and is in critical condition, reports said. "He went to the garage, he obtained a large hammer". "She was covered in blood", said the neighbor.
The father of Janel Simpson, Denis Simpson, told NBC that she went to her friend's home after working late.
He described his daughter and her friends as fun-loving women who went to Carnival in Trinidad and were planning to visit Cuba in the fall.
He's been arrested before for DWI and sexual abuse.
Sunday morning he will be arraigned on three counts of murder and one count of attempted murder.