NAPERVILLE, Ill. (CBS) — Court filings suggest a financial motive in the murder of a Naperville woman, allegedly at the hands of her brother.

As WBBM Newsradio’s Mike Krauser reports, Cathleen Lewis, 59, and her mother, withheld the disability check for Mark Lewis, 51, on June 5, three days before Cathleen was beaten to death with a hammer, according to the court filings.

LISTEN: WBBM Newsradio’s Mike Krauser reports

Mark Lewis was found in outside a drugstore in Pensacola, Fla., month later, and police may have tracked him through his online searches for news of the murder before it went public. Police sought records from Google and Yahoo of searches using the terms “Cathleen Lewis Murder” and “Cathleen Lewis Naperville” on dates before her death became public.

A cousin discovered Cathleen Lewis’ body in her bed in the 2300 block of Worthing Drive in Naperville June 8, police said. Though the family member initially thought Cathleen Lewis committed suicide, police said the pillows on her bed had likely been moved because one had blood underneath it.

Police also said they found no signs of forced entry from the front door, and the home seemed clean. The kitchen cabinets and drawers were mostly open, and it appeared someone had gone through them. Though their mother lived in the townhome, she wasn’t home at the time of the killing.

Family members described Mark Lewis to police as a “paranoid schizophrenic” and a “degenerate gambler,” records show. He’d been feuding with Cathleen Lewis since at least March 22, police said, when she and their mother told the Naperville Police Department they went to his Lakemoor apartment and found a loaded rifle and maps from his home to Naperville.

He repeatedly questioned his mother and sister about money left behind after his father’s death. Then, in April, he showed up at their Naperville home with a video camera, pointing it around the residence as he walked around. He also took out a disposable camera to take pictures. A few weeks later, when his mother and sister visited his Lakemoor home, he pulled out the video camera again and began asking about his inheritance.

Mark Lewis also was upset that his sister had power of attorney over their mother, according to the filings. He was facing eviction when his mother and sister stopped depositing $300 from his government disability money into his bank account. The money, which Mark Lewis received because of his mental issues, usually would be deposited directly into his mother’s bank account. She would give him $300 on the 5th and 20th of every month.

That ended June 5. But shortly after Cathleen Lewis’ murder, police said, records showed $3,000 worth of checks were written from their mother’s bank account to Mark Lewis’. Their mother denied writing the checks, but police said surveillance video at one bank clearly shows Mark Lewis cashing them.

Examiners from the Will County coroner’s office concluded Cathleen Lewis died of “cranial cerebral injuries due to blunt head trauma.”

The Naperville Sun contributed to this report, via the Sun-Times Media Wire.

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