Chicago police has found a gun near the spot where Jennifer Hudson’s young nephew was found dead and it matches the caliber of the weapon used to kill him as well as his uncle and grandmother.

Police analyzed the .45-caliber weapon found Wednesday in an alley just a block away from where 7-year-old Julian King was discovered shot to death and left in the back seat of an SUV and say the ammunition recovered from the gun matches shell casings found at the murder scenes. The gun was found in thick shrubs, along with some “small bits” of evidence the police has not detailed.

A law enforcement source told the Chicago Tribune it is the same weapon used to kill 57-year-old Darnell Donerson and 29-year-old Jason Hudson, mother and brother, respectively, to actress Jennifer Hudson, on Friday, Oct. 24. The two were found dead inside their home in Chicago’s South Side by a relative.

An Amber Alert was soon issued for Julian King, Jennifer Hudson’s nephew, who was missing. The little boy was discovered Monday, inside the abandoned SUV, on the city’s West Side. He had been shot multiple times. The Academy Award winner had offered a $100,000 reward for Julian’s safe return…

William Balfour, the 27-year-old stepfather of Julian and estranged husband of Hudson’s sister, Julia Hudson, became a person of interest for authorities shortly after the bodies were discovered. On Saturday, the Illinois Department of Corrections issued a warrant for Balfour for violating terms of his parole by possessing a weapon and not attending anger management classes and a substance abuse program.

Balfour served nearly seven years in jail for attempted murder and vehicular hijacking. He was released in 2006. In June, he was arrested when police officers found crack cocaine in his car but his parole was not revoked by the corrections department and the charges were eventually dropped.

Balfour has denied any sort of involvement in the crimes. He told police officers he had a good relationship with the Hudson family, a police source told the Associated Press Wednesday, on condition of anonymity.

The convicted felon’s mother had previously told the media that her son was innocent and that he had been ordered out of the Hudson home the previous winter by Darnell Donerson.

The same source told the AP that when invited to take a polygraph test, Balfour refused to cooperate any further and declined the test.

As of Wednesday, Balfour had not been charged with any crimes. He remains in custody on a parole violation.