Camden County prosecutors said 6-year-old Dominick Andujor was pronounced dead at the scene, but did not release further details on the slaying. His sister, whose throat was slit, remained hospitalized.
The girl, whose name was not released, went door to door in her Camden neighborhood to get help and finally reached the home of Nakyta McCray, who called 911. McCray said the girl "was barely breathing" and bleeding profusely when emergency personnel arrived.
The boy's father lives out of state, authorities said, and his mother was in the hospital at the time. It wasn't clear yet why the children were targeted, but a man who lives in the area and apparently has lacerations on his hand was being sought Sunday.
Also in the home were two girls, ages 9 and 14, said Jason Laughlin, a spokesman for the Camden County prosecutor's office. The teenager had been babysitting the other three children because of her hospitalization.
Further details on the girl's injuries and the stabbings, including what type of weapon was used, were not disclosed.
The girl was taken to Cooper University Hospital, but officials there would not discuss her condition, citing privacy issues.
McCray said the man she believed police were looking for is well-known around the neighborhood. She said he plays with the local children and seems to be a peaceful person.
"People would never think he would do something like this," she said. Camden, across the Delaware River from Philadelphia, continually ranks as one of the nation's most dangerous. The double stabbing comes shortly after another child died a violent death in Camden. On Aug. 22, a 33-year-old city woman allegedly decapitated her 2-year-old toddler and then fatally stabbed herself.
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