By Joshua Rich
Updated July 30, 2020 at 01:20 PM EDT

Chicago police have arrested William Balfour, Jennifer Hudson’s estranged brother-in-law, in the October killings of her mother, brother, and young nephew. Balfour, 27 — who is separated from Hudson’s sister, Julia — was transferred from an Illinois prison, where he had been held for a possible parole violation, to police custody on Monday. Formal charges have not yet been filed, reports.

The Academy Award winner and American Idol alum’s mother, Darnell Donerson, 57, and brother, Jason Hudson, 29, were found shot to death in the family’s home on Oct. 24. Three days later, the body of 7-year-old Julian King, Julia Hudson’s son and Balfour’s stepson, was found in a car 10 miles away. Shortly after the murders, Balfour had been detained for questioning.