Money motivated a Suffolk County man to fatally stab his uncle, according to police.

They say David Cahoon Jr., 40, stabbed his uncle last December 18 times, including nine times to the head and face. The uncle, 70-year-old William Cahoon, was found dead in his Levittown home a month later, when staff at the Milleridge Inn went to check on him, noticing he hadn't come in for his weekly dinner for a while.

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Detectives say William Cahoon "had a substantial amount of money," accrued from various sources.

Police arrested David Cahoon Wednesday afternoon at this home on Lone Hill Place in Dix Hills. Prosecutors say he had gone into hiding, renting a basement apartment, clearing out his bank accounts, changing his cellphone number and using aliases.

In January, the suspect's mother had come to the crime scene and told News 12 that she couldn't imagine who would want to kill her brother-in-law.

On Thursday, Ellen Cahoon had nothing to say. But David Cahoon's attorney said his client "is a convenient patsy."

The prosecutor said in court that when David Cahoon went into what they called hiding, he abandoned his dog in his Huntington apartment. His attorney said he had been in touch with police since March when he was first hired, and his client never left Long Island during the investigation.

David Cahoon was held without bail.