Phone records for two mobile numbers were being examined Monday as investigators probing the killing of a Texas prosecutor and his wife sought possible links to the January slaying of another area district attorney and amid suggestions that a white supremacist was involved.

Authorities are looking at records for the two mobile numbers between Jan. 1 and Sunday, according to details of a search warrant, made public Monday and reported by NBCDFW.com. No more details were given in the warrant.

Kaufman County District Attorney Mike McLelland and his wife, Cynthia, were gunned down at their home outside Dallas on Saturday. The county’s Assistant District Attorney Mark Hasse was shot dead near the county courthouse on his way to work on Jan. 31.

The search warrant also revealed that the McLellands’ bodies were initially found by a family friend who went to the residence after trying to contact the couple several times without success.

The slayings have dismayed residents in the county, particularly in its main town, Kaufman.

"People are in absolute shock here," Joe Gibson, 21, the manager at Moon's Fried Chicken Cafeteria told Reuters.

Insurance agent Bobby Aga, 68, told Reuters: “We have a strong tradition of law enforcement in this area. The criminal justice system here is something you don't mess with. It's the fabric of our community."

Authorities have not said the killings are linked and have not announced any leads in the McLellands’ deaths – although a county judge, Bruce Wood, said Monday that "there has to be some connection."

Several people who are familiar with the case downplayed any possible connection to white supremacist prison gang, the Aryan Brotherhood of Texas, NBCDFW.com reported. Investigators say they have found nothing to indicate the Aryan Brotherhood was involved.

However, Rep. Ted Poe, a Republican and former Texas prosecutor, told CNN on Monday that he suspected the gang was involved, without saying where he was getting his information.

On the day Hasse was killed, the Kaufman County DA’s office was named among the investigative bodies involved in a racketeering case against the gang.

The hate group was suspected of “actively planning retaliation” against police and prosecutors who helped gain indictments in Houston against dozens of its members, the Dallas Morning News reported in February.

The Aryan Brotherhood has been in the state's prison system since the 1980s, when it began as a white supremacist gang that protected its members and ran illegal activities, including drug distribution, Terry Pelz, a former Texas prison warden and expert on the gang, told the Associated Press.

Four top leaders of the group were indicted in October for crimes ranging from murder to drug trafficking. Two months later, authorities issued the bulletin warning that the gang might try to retaliate against law enforcement for the investigation that also led to the arrest of 30 other members.

Hasse's death on Jan. 31 came the same day as the first guilty pleas were entered in the indictment, the AP reported.

Killing law enforcement representatives would be uncharacteristic of the group, Pelz said.

"They don't go around killing officials," he said. "They don't draw heat upon themselves."

Late Monday, Kaufman County Sheriff's office announced that Brandi Fernandez, First Assistant District Attorney, will fill the position of interim DA for a period of 21 days.

The murders serve as a reminder that officers of courts across the nation continually face threats, although these are rarely carried out.

Reuters and The Associated Press contributed to this report.

Related:

Texas community in 'shock' over slaying of DA, wife

District attorney, wife shot to death in Texas county where assistant DA was killed

This story was originally published on Tue Apr 2, 2013 4:53 AM EDT