CHICAGO - An Illinois man charged with murder and hate crimes for stabbing a six-year-old Muslim boy to death and wounding his mother pleaded not guilty before a judge on Monday at an arraignment, according to court records.

Police say Joseph Czuba, 71, the family's landlord, targeted them for their religion and as a response to the war between Israel and Hamas, police said.

His attorney George Lenard entered the plea for him and Czuba, appearing in a red jail uniform, did not speak, an NBC News affiliate in Chicago reported on Monday.

He is charged with the fatal stabbing of Wadea Al-Fayoume, 6, and the wounding of his mother Hanaan Shahin, 32, on Oct 14, in Plainfield Township, about 64km south-west of Chicago.

The boy was stabbed 26 times with a military-style knife with a 18cm serrated blade, the Will County Sheriff's Office said in a statement.

Czuba's attorney was not immediately available to Reuters for comment on Monday. Mr Lenard has previously told the media that he will not comment outside the courtroom.

Czuba entered the plea at an arraignment in Joilet, about 80km south-west of Chicago, on eight counts, including first-degree murder, attempted first-degree murder, aggravated battery with a deadly weapon and hate crimes.

"Detectives were able to determine that both victims in this brutal attack were targeted by the suspect due to them being Muslim and the ongoing Middle Eastern conflict involving Hamas and the Israelis," the Will County Sheriff's Office said in a statement earlier.

He remains in jail with no bond allowed, court records say.

The Department of Justice has also opened a federal investigation into Al-Fayoume's death. REUTERS