A Rock Island man accused of fatally striking his grandmother and uncle in the head and cutting their throats Sunday night in Rock Island is expected to make his first court appearance in Rock Island County Court Wednesday.

John Patrick Conwell, 39, was arrested Monday afternoon in Davenport on two counts of first-degree murder in the deaths of Eleanor M. “Petty” Conwell, 90, and Steve D. Conwell, 69.

John Conwell appeared briefly in a Scott County courtroom via closed-circuit video Tuesday morning and waived extradition.

Online jail records show that he was released from the Scott County Jail and into the custody of Rock Island County at 10:25 a.m.

Police were called at 7:54 p.m. Sunday to the 1200 block of 29th Street for a welfare check and found the bodies of Eleanore and Steve Conwell.

Prosecutors allege in charging documents that John Conwell "knowingly and without justification" struck Eleanor and Steve Conwell in the head and cut their throats.

Their deaths resulted from "exceptionally brutal or heinous behavior indicative of wanton cruelty," according to the documents.

Preliminary results of an autopsy conducted in Dixon, Illinois, Tuesday reveal that the Conwells died from blunt trauma to the head and stab wounds to the neck, Rock Island County Coroner Brian Gustafson said.

John Conwell was arrested Monday afternoon in the area of 2nd and Ripley streets in Davenport.

Bond on the warrant was set at $5 million cash-only.

If convicted, he faces up to life in prison.