US actress Jennifer Hudson's brother-in-law has been charged with murdering three of her relatives.

William Balfour, 27, was formally charged with three counts of first degree murder over the shootings of Hudson's seven-year-old nephew Julian King, her mother and her brother.

The bodies of Darnell Hudson Donerson and Jason Hudson were discovered in their Chicago home on October 24 before the child's body was found in a sport utility vehicle three days later.

Balfour, who served seven years for a 1999 attempted murder and carjacking, has been in custody on a parole violation since the first two bodies were discovered in October.

Police formally arrested him on a warrant in the deaths yesterday before he was charged today.

Balfour's lawyer Joshua Kutnick said: "He vehemently denies that he is guilty in this case. Any evidence pointing to Mr Balfour is not even thin. It is very, very weak."

Balfour is Julian's stepfather and the estranged husband of the Oscar-winning actress's older sister, Julia Hudson.

Jennifer Hudson was a finalist in the 2004 season of TV singing competition American Idol and won an Oscar in 2007 for a supporting role in Dreamgirls alongside Beyonce Knowles.

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