Brandi Fernandez, who has replaced the district attorney murdered in North Texas on the weekend, vowed that her staff would vigorously pursue cases despite the dangers.

At a press conference on Thursday, Fernandez, who is serving on an interim basis, conceded that her staff is "unnerved" but will continue to adhere to their oath to serve the community.

Fernandez said that the killings of Kaufman County District Attorney Mike McLelland and his wife Cynthia on Saturday, and the killing Jan. 31 of Kaufman County Assistant District Attorney Mark Hasse, have not slowed prosecution efforts by her office.

Fernandez says she's proud of assistant prosecutors as they continue their work despite the killers remaining at large.

Meanwhile, law enforcement members attended the memorial service for the McLellands. Gov. Rick Perry was among those who spoke Thursday at the service. Perry said the McLellands were aware of the dangers of his job but his determination to "do right" by the people of Kaufman County wasn't diminished.

Perry says Hasse's death weighed "heavy" on the McLellands' minds and hearts. And he says they were too vibrant and full of life to be gone so quickly. Hasse was gunned down outside the county courthouse while arriving for work.

Perry also announced a $100,000 reward to help find the killers of the McLellands.

Perry's announcement joins a similar reward offered by Kaufman County Crime Stoppers after Hasse was slain on Jan. 31.

Hasse was gunned down outside the county courthouse while arriving for work.

Authorities also have mentioned a possible link between the murders and the Aryan Brotherhood of Texas, a white supremacist prison gang described as one of the most violent in the jail system.

Authorities have told reporters that they believe the gang is bent on sending a message to law enforcement officials.

Fernandez has gone after the gang herself in the past.

Last year, she was the main prosecutor in the case of James “Wreck” Crawford, a top so-called “enforcer” of the Aryan Brotherhood of Texas, and managed to get him sentenced to two life terms.

This is based on a story by The Associated Press.

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