A woman’s estranged ex-boyfriend went her home, strangled her daughter and set fires to cover up the crime, police said.

Romulo A. Gregoria, Jr., 38, of Pearsall Avenue, was arrested in the homicide of Christine L. Mariano, 20, of 238 Stevens Ave. Sept. 2, police said.

“The fire was intentionally set in two areas in the bedroom to conceal the homicide,” said Hudson County Prosecutor Edward DeFazio. “(Gregoria) was the ex-boyfriend of the victims’s mother. “He was stalking the mom.”

The distraught mother, Claire, was working as a pediatric nurse at Christ Hospital in the Heights and rushed home when learning of the fire on Sept.1, around 4:15 p.m.

Gregorio had previously gone to the home and found the daughter.

“An argument escalated to a physical assault. There was a confrontation between the defendant and the victim.”

The victim, who was visiting her family after attending culinary school in Florida, was found in a second floor bedroom, with burns to her body. But the cause of death was quickly found to be strangulation, according to Medical Examiner.

There was no restraining order in place.