Villanueva then turned the blue-handled, serrated-edged pocket knife on Kristen DuRocher and at some point suffered some wounds himself before he fled, they said.
Suzanne DuRocher, a veteran nurse at Temple University Hospital, was rushed to Cooper University Hospital in Camden, where she was pronounced dead Wednesday night. Her daughter was admitted with serious stab wounds and was in stable condition Thursday.
Kristen DuRocher's daughter, about 3, was physically unharmed.
Police were called to the scene about 10:30 p.m. by a neighbor who found Kristen DuRocher at his door pleading for help.
Prosecutors later told a Superior Court judge in Camden that during the assault, Kristen DuRocher told investigators that Villanueva had told her "to just go lay with her mother."
On Wednesday, police swarmed the normally quiet neighborhood as news helicopters hovered over the scene. Meanwhile, in Camden, a security guard at Our Lady of Lourdes Medical Center flagged down a police officer. Villanueva, of Rand Street in Camden, had arrived there with stab wounds to his hand.
On Thursday afternoon, Villanueva appeared before Superior Court Judge Samuel D. Natal, where he was charged with murder, attempted murder, and burglary. His right hand was wrapped in a bandage and he appeared calm next to his Cherry Hill attorney, John A. Klamo as he pleaded not guilty.
He was remanded to the Camden County Jail with bail set at $1.75 million.
Assistant Camden County Prosecutor Howard C. Gilfert told the judge that Villanueva had told Kristen DuRocher that "he wasn't going to hurt her and that he just wanted to talk" as he stood in her room.
After he threw the screwdriver on the floor, she picked it up and tossed it to the other side of her bed. Then her mother confronted him.
Klamo said his client was unemployed but had worked for a Brooklawn restaurant. A woman who said she knew Villanueva but declined to give her name said Villanueva and DuRocher had met at the restaurant.
Klamo said his client has two children and a third on the way, but was not the father of DuRocher's child.
According to authorities, Villanueva and Kristen DuRocher had problems. Last month, DuRocher obtained a temporary restraining order against Villanueva, but withdrew it days later.
Gilfert said Villanueva's criminal history includes two convictions for terroristic threats as well as one for unlawful possession of a weapon. Authorities said that in 2006, a woman in Bordentown also obtained a restraining order against Villanueva.
On Wednesday night, after fleeing from the Merchantville home, Villanueva called his sister, authorities said.
"He asked her to pick him up and said that he was going to die," according to court records. "She found him on Route 130 and Marlton Pike, behind Dunkin' Donuts, bleeding."
Villanueva allegedly told his sister that he had stabbed the two women.
Neighbors of the DuRochers spoke highly of the family and said they were shocked by the crime. Suzanne DuRocher was associate chief nursing officer of operations at Temple.
"We are shocked and saddened by the criminal act that took the life of our dear colleague," according to a news release from Temple. "We extend our sincerest condolences to her family and friends as they begin to deal with the aftereffects of this tragic loss."
For eight years, officials said, Suzanne DuRocher was a member of the hospital's leadership team, focusing on providing advanced and compassionate care to patients.
"We have lost a wonderful and inspirational colleague whose passion for life and positive energy was expressed every single day," Temple's statement said, noting that DuRocher's "presence will be dearly missed."
On Prospect Street, a stream of neighbors stopped to find out what had happened. The DuRochers' home had Halloween decorations on the porch, along with strollers for several grandchildren.
"She was just a great lady," said Stephanie Maines, 28.
The family, neighbors said, has had a difficult time since the death of Suzanne DuRocher's husband, Robert, who was fatally injured at work in 2011.