TRENTON, N.J. — A man high on PCP-laced marijuana stabbed two neighborhood children in their home while they slept, killing a 6-year-old boy and critically wounding his 12-year-old sister, authorities said.

Osvaldo Rivera was found hiding between a mattress and a bedroom wall Sunday afternoon inside a Camden apartment and was charged Monday with murder and attempted murder, said Jason Laughlin, a spokesman for the Camden County prosecutor's office.

The attack was the second recent one in Camden, an impoverished city across the river from Philadelphia, involving a child and a suspect said to be high on PCP and marijuana.

Rivera, 31, was being held in jail awaiting arraignment, which Laughlin said will likely be held Tuesday. Laughlin didn't know if Rivera had an attorney.

Police found blood-stained sneakers inside the apartment where Rivera was arrested that matched bloody footprints in the home where Dominick Andujor was stabbed to death, Laughlin said. The boy's 12-year-old sister had her throat slit while she slept in the same room. She remained hospitalized Monday at Cooper University Hospital in Camden. The hospital, though, has declined to discuss her condition, citing privacy reasons.

While being questioned by investigators, Rivera said he had smoked a combination of marijuana and the hallucinogenic drug PCP before the attack, Laughlin said.

On Aug. 22, 33-year-old Chevonne Thomas of Camden allegedly decapitated her 2-year-old toddler and then fatally stabbed herself after smoking a similar combination, known as "wet."

Laughlin said there have been several other murders in recent years in which PCP-laced marijuana has apparently played a role. He said the drug combination makes people incoherent, hallucinatory and, in some cases, violent, adding that authorities plan to take steps to curb the drug's market.

The children stabbed Sunday were being watched by a 14-year-old girl, authorities said. The teen, who was unharmed, was caring for them because their mother recently underwent surgery and was still in the hospital.

Laughlin said the 12-year-old, whose name wasn't released, fled the home after the attack and was found at a neighbor's home a few doors down. Police soon went to the girl's home and were met by another child who ran outside, screaming for help for her brother. The 6-year-old boy was found lying on the floor.

While Rivera was still being sought on Sunday, a woman who lives nearby said he was well-known around the neighborhood and seemed to be a peaceful person. He also was often seen playing with the local children.

"People would never think he would do something like this," Nakyta McCray said.

Earlier on HuffPost:

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  • "Not Guilty as Sin" -NY Post

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  • "An American Tragedy" -TIME

    Known and heralded as the "trial of the century," former football star and actor O.J. Simpson found himself in the middle of the nation's biggest, most-televised trial following the deaths of his ex-wife Nicole Brown Simpson and her friend Ron Goldman, but not before fleeing an all-points bulletin in his Ford Bronco with 20 units in tow, interrupting game 5 of the NBA Finals. By enlisting a dream team including Johnnie Cochran, Robert Shapiro, and Robert Kardashian, the defense claimed Simpson was merely a victim of police fraud with regard to contaminated DNA evidence, while famously quipping "If it [the glove] doesn't fit, you must acquit." On October 3, 1995, an estimated 100 million people from around the world tuned in to watch the jury hand down a verdict of not guilty, consequently resulting in an estimated loss of $480 million in productivity and inciting an ongoing discussion of race in the judicial system that continues to this day.