Police searching for actress Jennifer Hudson’s missing seven-year-old nephew say they have found the body of a young black boy in a sports utility vehicle.

The missing child, Julian King, has not been seen since Friday, when Hudson’s mother and brother were found shot to death.

The bodies of Julian’s grandmother, 57-year-old Darnell Donerson, and his uncle Jason Hudson, 29, were discovered lying in the home they shared on the city’s South Side. Police issued an Amber Alert search notice for Julian and were looking for a 1994 white Chevrolet Suburban.

Hudson offered a $100,000 reward for her nephew’s safe return.

The Cook County Medical Examiner’s office and Chicago Police Department sent officials to the scene of a white SUV on the city’s West Side early today. There was no confirmation of the identity of the body, and police have so far refused to comment.

Television footage showed police vehicles escorting a flatbed tow truck as it took the SUV away from the scene. Police later said that the number on the license plate on the vehicle matched the number listed in their earlier alert.

Julian is the son of Jennifer Hudson’s sister, Julia Hudson. The police initially identified William Balfour, the estranged husband of Julia Hudson and stepfather of Julian King, as a suspect in the case. The 27-year-old baker has convictions for attempted murder, carjacking and possession of a stolen motor vehicle, according to the Illinois Department of Corrections.

He was released from prison in May 2006 and is still on probation. He was not living with his estranged wife at the time of the shooting. The couple had recently fought because Mr Balfour had sold Ms Hudson’s car without her permission, according to local media reports.

On Friday, Chicago police had taken Mr Balfour into custody for questioning over the deaths but the missing boy was not with him.

“We are doing that as a precautionary measure,” Superintendent Jody Weis, of the Chicago police, said in a television interview.

He added that the murders and the child’s disappearance seemed to be part of a domestic dispute. “From what we know right now, it appears to be some type of domestic situation but that is very preliminary. We just have to follow the evidence.”

Yesterday, Mr Balfour was transferred to the Illinois Department of Corrections “based on his active parole violation unrelated to this investigation.”

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