(CNN) -- A former Kaufman County, Texas, justice of the peace is accused of using his home computer to send a terrorist threat to police investigating the killing of the top county prosecutor and his wife, a sheriff's affidavit says.
Eric Lyle Williams, 46, was arrested and charged last week with two counts of insufficient bond and one count of making a terroristic threat, and the affidavit revealed the circumstances of the charges against him.
Authorities declined to provide details behind the charges last week, but the affidavit says that they believe Williams made the threat March 31, one day after police found the bodies of Kaufman County District Attorney Michael McLelland and his wife, Cynthia, both of whom were shot to death.
"The threat implied unless law enforcement responded to the demand of the writer, another attack would occur," said the affidavit by Richard Moosbrugger of the Kaufman County Sheriff's Office.
The threat was received "via electronic communication" by law officers investigating the two deaths, said the affidavit, which is dated April 12.
Moosbrugger says in the document that a search of Williams' home on Friday led to the discovery that he used "unique" electronic identifiers to send the threat from his personal computer.
Two search warrants obtained by CNN reveal additional details in the investigation. The warrants, issued hours before Williams was arrested, indicate that authorities searched Williams' home and another address on the same street for evidence that the county computer system was misused in connection with the killings.
The warrants say there was probable cause for alleged violations including "the abuse of official capacity concerning misuse of Kaufman County usernames and access codes to access Internet services."
The search warrants also say law enforcement could search the properties at any time of day without knocking first due to "circumstances involving the potential for the destruction of evidence and the significant risk to officer and public safety."
Williams is being held in lieu of $3 million bail -- $1 million for each charge he faces -- according to the sheriff's office.
A woman who answered the phone Tuesday at the Kaufman County jail said Williams had issued a statement refusing all media requests for an interview.
David Sergi, the attorney who has been representing him, could not be reached for comment.
Williams has a history with law enforcement authorities, including the Kaufman County district attorney's office.
Last year, he was sentenced to two years of probation after a conviction for burglary and theft by a public servant. Hasse prosecuted Williams' case.
Hours after the McLellands' bodies were found, authorities met with Williams at a local Denny's, Sergi said this month.
Investigators took swabs of Williams' hands to test him for gunshot residue, according to the lawyer. Results were not made public by officials, but Sergi said the tests came back negative.
On Friday, Sergi released a statement saying that Williams "has cooperated with law enforcement and vigorously denies any and all allegations. He wishes simply to get on with his life and hopes that the perpetrators are brought to justice."
Williams told North Texas TV station KXAS this month that he understands why authorities wanted to meet with him.
"If I was in their shoes, I would want to talk to me," he said. "In the investigators' minds, they want to check with me to do their process of elimination."
Williams said he has no ill will toward prosecutors -- they were "doing their jobs," he said -- and has cooperated with law enforcement.
"I certainly wish them the best in bringing justice to this incredibly egregious act," he said.
CNN's Tristan Smith contributed to this report.