( CNN ) -- A New Jersey man is accused of killing a 6-year-old boy and seriously wounding the boy 's 12-year-old sister , Jason Laughlin of the Camden County Prosecutor 's Office said Monday . Osvaldo Rivera , 31 , was arrested Sunday afternoon and charged with murder and attempted murder , the prosecutor 's office said in a news release . Dominick Andujar was found dead with his throat slit in a home in the city of Camden , officials said . His sister suffered stab wounds and fled to a neighbor 's home after the attack . She is in critical condition at Cooper Hospital in Camden . Investigators said Rivera , who lives in the area and goes by the nickname `` Popeye , '' was discovered in an apartment on the north side of the city , hiding between a mattress and a bedroom wall . He was found with blood-stained sneakers that appeared to match bloody footprints in the victims ' home , the prosecutor 's office said . `` Several citizens came forward and showed the courage to provide information , which helped lead to the initial apprehension , '' Camden County Prosecutor 's Office Lt. Frank Falco said . Rivera told investigators he had smoked `` wet , '' a combination of marijuana and PCP , before the killing , the prosecutor 's office said . This marks the second time this drug combination has been connected with the slaying of a child in Camden , the office said . Chevonne Thomas is believed to have been smoking wet prior to allegedly beheading her son , Zahree , on August 22.. Rivera is being held at the Camden County Jail , the prosecutor 's office said , and an arraignment is expected Tuesday . Attempts to contact an attorney for comment were unsuccessful Monday . Laughlin , of the prosecutor 's office , said it appeared Rivera did not yet have an attorney .
A 6-year-old boy is dead and his 12-year-old sister is seriously injured . Osvaldo Rivera , 31 , is charged with murder and attempted murder . He told prosecutors he was under the influence of `` wet '' -- marijuana with PCP .