David Crone and his wife were friends with their next-door neighbors, Mike and Cynthia McLelland. They enjoyed life in their quiet, idyllic neighborhood east of Dallas.
Tuesday, crime scene tape separating their homes showed that not all was well and peaceful.
Deputies and other investigators continued their search for evidence at the home of Mike McLelland, district attorney for Kaufman County. The prosecutor and his wife were were killed there over the weekend.
Friends discovered their bodies Saturday, nearly two months to the day after someone killed McLelland's chief felony prosecutor, Mark Hasse, in a daytime shooting outside the county courthouse January 31.
The Crones were at home during the time frame in which their neighbors were slain.
"I never heard anything," David Crone told CNN on Tuesday. His dogs were outside part of the time and never barked, he said. A storm passed through early Saturday, he said.
The resident said a neighbor who lives farther away claimed to have heard gunshots.
Crone said he and Mike McLelland were members of a rifle and pistol club.
As state and federal investigators flood this north Texas county searching for clues in the killing of two prosecutors in two months, the 100,000 people who live here can do little but nervously watch and hope.
"The residents are, I think, astounded," said Delois Stolusky, who has lived in Kaufman, the county seat, for 30 years. "It's just, one and one make two. You can't keep from connecting these. And it's just scary because we have no clue of who did the first shooting. And no clue, of course, yet, who did this one. And so, of course, our concern is what's going to happen next."
The killings have also rattled law enforcement officials, leading to increased security at the Kaufman County courthouse and around the county's elected leaders.
"I can promise you that all of the people in this courthouse, all of the elected officials, all of the other people who are involved in this investigation, are being very well-protected," County Judge Bruce Wood told reporters Tuesday.
Wood said "literally hundreds" of investigators are working the case.
"I'm not sure what time frame we're on, but I'm confident that they will find whoever committed this crime," he said.
The investigation is starting from scratch, with no leads in the McLellands' deaths, CNN affiliate WFAA reported.
Nor do officials have any further ideas on who killed Hasse.
McLelland talked to relatives on Friday night, a search warrant affidavit said. Investigators have asked a judge for records of mobile phone calls that were relayed through at least one nearby tower, the documents show.
Law enforcement analysts say they believe those behind the attacks had been monitoring and following the two prosecutors, given the locations of the attacks and the brazenness of killing the men where they were most comfortable.
The killings have put justice officials across the state on high alert, unsure if or when another such strike might occur.
"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.
Some, like Harris County's district attorney in Houston, are now under 24-hour security.
McLelland himself had a sheriff's deputy guarding his house after Hasse's death. Exactly why the deputy stopped patrolling the home is unclear.
CNN affiliate KTVT said the sheriff's department removed the security detail because McLelland thought it was unnecessary and didn't want to waste taxpayer dollars.
But sources told WFAA a deputy was dispatched to McLelland's home only as a temporary assignment. The home was equipped with surveillance cameras, but not the kind that constantly record, the affiliate said.