Citing a federal official it did not name, the Los Angeles Times reported Tuesday investigators were scrutinizing the former local official, who was dismissed after being arrested for alleged possession of stolen goods in connection with a corruption investigation. The former official was prosecuted by Kaufman County District Attorney Mike McLelland, 63, who was shot and killed at his home along with his wife, Cynthia, 65, during the weekend.
Assistant prosecutor Mark Hasse, who was shot and killed Jan. 31, also was involved in the prosecution of the local official, who subsequently threatened to retaliate against McClelland and allegedly threatened to burn down the home of another official, the Times reported.
Authorities have said they were starting virtually from scratch in the investigation into the killing of the McClellands and Hasse, WFAA-TV, Dallas, reported Tuesday.
Justice officials across the state are on high alert, unsure if or when a similar attack might occur, CNN said.
"This, I think, is a clear concern to individuals who are in public life, particularly those who deal with some very mean and vicious individuals -- whether they're white supremacy groups or drug cartels that we have," Texas Gov. Rick Perry said.
McLelland's office was one of many Texas and federal agencies involved in a multiyear investigation that resulted in the indictment last year of 34 alleged members of the Aryan Brotherhood of Texas on racketeering charges.
The possibility has been raised the McLellands' and Hasse's deaths may be linked to white supremacists, CNN and other media outlets said.
Pete Schulte, a friend of McLelland, expressed astonishment about the attacks in Kaufman County, a largely rural area east of Dallas.
"Everybody knew each other here," Schulte told CNN. "Everybody liked the district attorney's office. There just wasn't a lot of activity out here.
"So the biggest shock out here ... is why, in Kaufman, Texas, are we having an assistant DA get killed and an elected DA?" Schulte said. "It's really sending some shockwaves through the community."
Law enforcement analysts said they think the people behind both attacks were monitoring and following McLelland and Hasse.
Hasse was killed in daylight hours Jan. 31 while walking from his car to the courthouse.
The McLellands were shot multiple times in their home. Their bodies were found Saturday by friends who tried to contact them several times during the day.
A public memorial for the couple will be held Thursday. A funeral was scheduled Friday.