But how and why the standoff occurred is just one of the many questions that law enforcement officials are working to resolve.
The standoff at the South Trenton home ended early Sunday when police stormed the residence and confronted 38-year-old Gerald "Skip" Tyrone Murphy in an upstairs bedroom. An officer then shot Murphy because he was threatening one of the children.
State police Col. Rick Fuentes said the decision to enter the home was made because officials grew more concerned about Murphy's "deteriorating state of mind" and to help ensure the captives survived. Murphy had kept the captives with him inside the roughly 10-foot-by-11-foot bedroom throughout the standoff, "This was a very complex matter, considering the space (where the hostages were) and that three children were involved," Fuentes said during a news conference. "Our mission over those 37 hours was to save innocent lives."
Officers initially went to the home Friday afternoon after a relative of 44-year-old Carmelita Stevens said she hadn't spoken to her in weeks and was worried. Upon further investigation, authorities discovered her children hadn't been to school in 12 days.
Murphy and Stevens had been dating for a few months, and both lived in the house, police said. Murphy was not the father of any of her children Police entered the home through a rear door and smelled an odor consistent with that of a decomposing body. They also noticed maggots throughout the residence.
When they found Murphy in an upstairs bedroom, he told them he was armed with a gun and explosives and had three children with him. Officers noticed one of the dead victims before they retreated from the second floor and rescued Stevens' 19-year-old son from the basement, who said he hadn't seen her or his siblings since about April 24. Authorities said he is autistic.
Three of Stevens' children - an 18-year-old woman, a 16-year-old girl and a 4-year-old boy - were rescued and taken to a medical center for evaluation and treatment, Mercer County Prosecutor Joseph L. Bocchini Jr. said.
The bodies of Stevens and her 13-year-old son were found in the house.