The Good Samaritan who witnessed the attack "jumped on [the assailant], picked up the knife and chased him off with the help of children who were present," Deputy Police Chief Gregory Halstead said.
Two responding officers quickly administered first aid, while two colleagues found Ernesto Dominguez-Hortelano, 37, hiding in a shed attached to a garage on the block behind the victim's home.
Dominguez-Hortelano claimed he was picking up a package when he came to his ex-girlfriend's apartment before 8:30 p.m., Halstead said.
"The residents were reluctant to admit him, but he forced his way in," the deputy chief said.
A struggle ensued and everyone involved ended up on the front porch, he said.
Dominguez-Hortelano then pulled a knife and repeatedly stabbed the woman, puncturing her lung and wounding her on the forearm, Halstead said.
That's when the neighbor jumped in.
At the scene, Officers Dona Nidelko and Dylan Donegan applied pressure to the victim's wounds to stop the bleeding and assisted emergency medical personnel who arrived soon after, the deputy chief said.
City Detective Ana Bedoya rode in the ambulance with her to Englewood Hospital and Medical Center, he said.
"Although her wounds are serious, she's expected to pull through," Halstead said shortly before midnight.
Officers Maciej Mlynaryk and Fabian Gallego canvassed the area on foot, going house to house from West Palisade Avenue into the backyards of Brookway Avenue and Mattlage Place, before finding Dominguez-Hortelano .
They took him into custody without incident, the deputy chief said.
Dominguez-Hortelano was being charged with attempted murder, armed burglary, three counts of child endangerment and weapons offenses, among other crimes, Halstead said.
The stabbing occurred on a street that in recent years has been rife with trouble.
YOU READ IT HERE FIRST: Four men, most of them from North Bergen, were arrested and charged with murder and other offenses Monday in the killing of a Fairview man during a weekend robbery at his home. A fifth was charged with hindering the investigation.
Mattlage Place, which runs all of four blocks, and a few surrounding block near the downtown commercial district have had several shootings in recent months.
Police were still trying to find whoever shot a woman in the foot and sent a bullet flying through the wall of a neighborhood home where several children were sleeping in April.
There have also been several drug arrests.
Last August, police raided a Mattlage Place apartment where they said a couple with four children had crack and pot.
Last month, they chased down a man who they said peppered a house with paintballs from what looked like a genuine weapon.
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