Kaufman County, Texas (CNN) -- It's been five days since Kaufman County's top prosecutor and his wife were found shot to death in their own home.
Five days of fear as the killer or killers remain at large.
Five days of wondering whether another criminal justice official might be the next target.
If authorities are any closer to solving the homicides of District Attorney Mike McLelland, his wife Cynthia, or his chief felony prosecutor, Mark Hasse, they haven't said so publicly.
But county government offices will shut down Thursday to give the community a chance to honor the McLellands at a public memorial in nearby Sunnyvale, Texas.
A funeral will follow on Friday, marking another solemn chapter in this harrowing saga.
KAUFMAN COUNTY DA MEMORIAL: LIVE at 12:30 p.m. until 3:30 p.m.
Here's the latest in the investigation:
New reward offered
Officials will announce Thursday a reward of up to $200,000 for information leading to the arrest and indictment of the killer or killers responsible for the McLelland or Hasse deaths, the head of Kaufman County Crime Stoppers told CNN.
President Tassie Gamble said the group had already poured virtually all of its reserves and donations -- about $100,000 -- into a reward after Hasse was killed in January.
But the stunning news of the McLellands' deaths prompted a renewed plea for donations, and the group has been working with Texas Gov. Rick Perry's office to boost reward donations, Gamble said.
Gamble hopes that if the assailants don't talk, the money will.
"There's always somebody out there who knows something," she said.
No clear suspects
"We haven't come close to charging anyone," a law enforcement official -- speaking on condition of anonymity -- told CNN on Wednesday. The official was not authorized to publicly release details of the investigation.
Authorities are considering a wide array of potential culprits -- such as a white supremacist gang targeted by officials last year to drug cartels to someone who may have held a personal grudge.
The official said McLelland was shot more than a dozen times.
Investigating local residents
Since Hasse was gunned down near the county courthouse January 31, authorities have pored through his case files, including public corruption cases, to see if any defendants he tried may have sought vengeance.
Authorities met with Eric Williams, a former justice of the peace who was convicted last year of burglary and theft by a public servant.
Surveillance video showed Williams apparently stealing computer monitors from the county courthouse. He was sentenced to two years' probation.
Saturday night, hours after the McLellands were found dead in their home, investigators met Williams at a local Denny's restaurant, his attorney told CNN Tuesday.
Investigators took swab samples from Williams' hand to test for gun residue, attorney David Sergi said.
The law enforcement official said Williams is not considered a leading suspect. Williams is "one angle we are looking at," the official said.
Sergi says his client voluntarily cooperated because he has nothing to hide.
Another Kaufman County resident has drawn the interest of investigators.
The man, who has been trying to open a gun range on his property, was involved in a civil dispute with McLelland and the county.
The resident told CNN that FBI agents visited him and asked a few questions, but nothing else materialized.
Speculation about the Aryan Brotherhood of Texas
McLelland, in an interview with The Associated Press before his death, speculated that the Aryan Brotherhood of Texas could have been behind Hasse's slaying.
"We put some real dents in the Aryan Brotherhood around here in the past year," McLelland told the news agency.
McLelland said Hasse wasn't involved in the Aryan Brotherhood of Texas investigation, but his office was one of numerous Texas and federal agencies involved in an investigation that led to the indictment last year of 34 alleged members of the group -- including four of its senior leaders -- on racketeering charges.
Authorities have not said whether they have linked white supremacists to the deaths. But weeks after the indictment, the Texas Department of Public Safety said it had "credible information" the Aryan Brotherhood of Texas was planning to retaliate.
When asked about the group's possible involvement, the governor said it was too soon to link or discount the ABT.
"I think it's obviously too early to be speculating on whether there is any direct contact, but I think it's wise for us to not overlook any evidence that either may be superficial or otherwise," Perry said on Fox News.
"So they are here, they are active in this state. We know the drug cartels are very, very active in our country now," Perry said.
Caller threatens to harm
As investigators search for leads in the case, authorities say a man called in a threat to a tip line, naming a county official as the next victim.
Authorities arrested Nick Morale, 56, on a charge of making a terroristic threat after he allegedly threatened a county official, Lt. Justin Lewis of the Kaufman County Sheriff's Office said Wednesday.
An arrest affidavit alleges that Morale called the county's Crime Stoppers tip line Monday afternoon, saying that a county official "would be the next victim."
Lewis said there was "nothing to link" Morale to the slayings of McLelland, his wife or Hasse.
Morale was behind bars Wednesday with bond set at $1 million, Lewis said.
Authorities declined to release the name or position of the county official who was threatened.
Gary Tuchman and Ed Lavandera reported from Kaufman County; Holly Yan reported and wrote from Atlanta. CNN's Carol Cratty and Vivian Kuo also contributed to this report.