Jennifer Hudson arrives during the "Sex And The City" movie premiere at Radio City Music Hall in New York, May 27.- Xinhua/Reuters

Chicago police confirmed that the body found inside a SUV yesterday morning was Oscar-winning actress Jennifer Hudson's 7-year-old nephew, who had been missing since Hudson's mother and brother were slain last week.

Julian King had been missing since Hudson's mother Darnell Donerson, 57 and brother Jason Hudson, 29 were found shot to death in their home Friday. Police spokeswoman Monique Bond said the boy also had been shot and the medical examiner's office planned a Tuesday autopsy.

Julian's body was found shortly after 7 am in the rear seat of the SUV abandoned on a Chicago street.

Chicago Police Superintendent Jody Weis said a motive remained unclear Monday but added the slayings appeared to be part of a domestic disturbance, but Weis declined to speculate on a motive.

Weis said William Balfour, 27, "remains a person of interest," as he had been taken into custody and was being held for a parole violation.

Balfour had a relationship with Hudson's sister Julia but is not the father of the missing boy. Balfour's mother said earlier her son and Julia were estranged and that he had nothing to do with the slayings.

Balfour was taken into custody for questioning Friday after the bodies of Hudson's mother and brother were found.

Corrections records show Balfour spent nearly seven years in prison for attempted murder, vehicular hijacking and possessing a stolen vehicle.

Hudson, 27, won a Best Supporting Actress Oscar for her portrayal of Effie in the film version of the Broadway musical "Dreamgirls." She gained fame as a contestant in 2005 on the top-rated US television show "American Idol." She placed seventh in the show's third season.