Authorities would not discuss how Kaufman County District Attorney Mike McLelland and his wife, Cynthia, died or whether their deaths were linked to the Jan. 31 fatal shooting of Mark Hasse, the assistant district attorney.
Police, FBI agents, Texas Rangers and Kaufman County sheriff's deputies were investigating the deaths. Kaufman is just east of Dallas.
The Dallas Morning News reported that Police Chief Chris Aulbaugh said the McLellands had been shot in their home and that although investigators didn't know if their deaths and Hasse's were related, they couldn't discount it.
Aulbaugh recently said that the FBI was looking into the possibility that Hasse's killing could be related to the March 19 killing of Colorado Department of Corrections head Tom Clements, who was gunned down after answering the doorbell at his home.
Evan Spencer Ebel, a former Colorado inmate and white supremacist who authorities believe killed Clements and a pizza deliveryman two days earlier, was gunned down in a March 21 shootout with Texas deputies about 100 miles from Kaufman.
Aulbaugh said after Ebel was killed that the investigation into whether the Hasse's and Clements' deaths were linked was routine for attacks that appear similar. Both targeted law enforcement officials. Authorities have investigated whether Hasse's death could be linked to a white supremacist gang.
The Associated Press contributed to this report.