A day before her 74th birthday, Vera Pecoraro was found dead in her Clark, N.J. home, her throat slashed with a serrated-blade knife that probably came from her house, police said.
It was the first homicide in Clark in 10 years, officials said.
Police believe she was targeted and probably knew her killer. Her body was discovered Saturday by one of her sons.
Robbery was not the motive, authorities said, and there were no signs of forced entry.
"It's a horrible crime," said Union County Prosecutor Theodore Romankow.
Medical examiners believe she was killed on Friday.
The victim and her late husband owned a street painting company, TSS --Traffic Safety Service, based in South Plainfield and run by two of their three sons.
"We do not believe that residents in the area are in any danger as we do not believe this is a random act," Romankow said in a statement.
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